Rabbi Yisroel Barkin Response to Rabbi Shlomo Miller on Techeiles

Responses to the Objections of the Gaon, Rav Shlomo Eliyahu Miller, shlit”a, Regarding the Identity of the Chilazon Today
Yisrael Barkin – Iyar 5774

I came across a letter from the esteemed Gaon, Rav Shlomo Eliyahu Miller shlit”a, Rosh Kollel Avreichim of Toronto and Av Beis Din of the Bais Hora’ah in Lakewood, concerning the techeiles produced today from the Porphyra sea snail known as Murex. This process is based on the research and writings of many recent authorities, such as the the Shiltei Giborim from R’ Avraham HaRofeh Portlaona, the Musaf HaAruch, the Chavos Yair, the Yaavetz, Rav S.R. Hirsch, and the Tiferes Re’em.

Rav Miller raised several strong objections to identifying this creature as the authentic chilazon, noting contradictions to seemingly explicit Gemaras. However, I later saw that a number of distinguished Torah scholars had written back with well-developed responses to those points. I reviewed their letters and the sources they brought at length. I thought it would be worthwhile to collect the answers to all of Rav Miller’s questions, adding in some of my own insights as well — although the vast majority of what I will present here is drawn from the work of others. Of course, I am nothing compared to the great Gaon shlit”a, but this is Torah, and I too have a responsibility to study and seek clarity. So I begin, with Hashem’s help.

At the start of his letter, Rav Miller wrote: “The process involves altering the secretion (rir) so that it appears just like Kala Ilan,”

It seems he used this wording in order to raise a question — namely, that the Gemara refers to “dam chilazon” (blood of the chilazon), while the fluid secreted by the Murex is not technically blood (at least based on what we currently know). However, it is not clear whether this secretion doesn’t in fact originate from the blood, perhaps having thickened into a mucous-like form. But in any case, this isn’t a strong question. We find that even other bodily fluids are sometimes referred to as “blood.” For example, in Nidda (41:2 “אמר רבי יוחנן מקור שהזיע כשתי טיפי מרגליות” ), Rabbi Yochanan says about tipin shel margoliyos (pearlescent drops), “they are white and clear blood,” and Rashi there explains that phrase as “white, clear blood.” Likewise, the Rambam (Rambam Hilchos Klei HaMikdash – the vessels of the Temple 1:3 ) refers to mor (myrrh) as “blood,” even though it’s not actual blood.

In fact, we find in common language that the secretion of the Murex was referred to as “blood” by Yosefon (Antiquities 3:7:7). And if the Torah speaks in human terms, then all the more so Chazal did as well.

One might still ask: if so, what was Tosafos’ question in Shabbos 75a (s.v. keiheichi)? They write: “It is difficult for R’ Yitzchak — after all, the extraction of blood should be considered taking a life.” But if the fluid isn’t animal blood, then what is the problem?

It would seem that this is exactly what Tosafos answer: “Rabeinu Tam replied that the blood used for dyeing is mifkad pakid (loosely contained and not absorbed), and one is not liable for that blood.” Meaning: the dam techeiles isn’t the kind of blood that causes liability for taking a life — rather, it’s a different type of bodily fluid, which is still called “blood” in the Gemara.

Nor can one object and say this isn’t definitive — that perhaps even animal blood can be mifkad pakid, and that Tosafos must have been assuming it was real blood, otherwise their question wouldn’t make sense, and maybe in their answer they changed that premise. But this isn’t correct. If you look closely at their language, they write: “Only that which is fit for dyeing is mifkad pakid,” which implies that other types of blood are not fit for dyeing. Only this particular type — the one that’s mifkad pakid — is fit for that use. That means we must say it’s a different substance entirely from standard blood.

Additionally, it’s not accurate to refer to the secretion as reir (slime), because reir specifically refers to something that drips. As Rashi explains on the pasuk in Shmuel I (21:14), “And his reir ran down his beard”: “His spit — something that drips is called reir.” And he gives other examples too, such as reir chalamos in Iyov 6:6 and rar besaro in Vayikra 15:3.

He further writes there: “the Gemara and Rambam clearly outline a test to distinguish between Techeiles and Kala Ilan (indigo). What they are calling the “new Techeiles” is practically identical to Kala Ilan, except that it is derived from the Murex species. The process involves altering the secretion so that it appears just like Kala Ilan, with no chemical distinction between them. Consequently, the traditional test to differentiate between Techeiles and Kala Ilan cannot be applied here.”

However, the claim that there is no chemical difference is factually inaccurate. In reality, kala ilan is primarily composed of a compound known as indigotin, and it contains a significant amount of indirubin as well, along with smaller traces of other substances. By contrast, the dye produced from the Murex snail also contains bromine compounds — a feature entirely absent in kala ilan. It does contain some indirubin, but in much smaller quantities compared to what’s found in kala ilan.

(Incidentally, some suggest that indirubin interferes with the bonding strength of the dye to wool.)

Even if, hypothetically, their chemical compositions were identical, that would still not prove that the strength of the dye’s attachment to wool would be the same. It’s well known that many other factors influence dye fastness besides chemical makeup. In fact, the Radbaz (Shu”t Radvaz (Siman 685) explicitly writes that over the generations, people developed improved methods to dye with istiss (which is another term for kala ilan) so that the color would hold stronger, even though the actual dyeing substance itself remained unchanged. That’s a clear proof against the assumption underlying the objection — because if dye strength were based solely on chemical composition, how could the strength of istiss dye have changed?

It is also a well-established historical fact that in ancient times, the dye extracted from the Murex snail was known to be extremely strong and durable, whereas kala ilan was not considered nearly as reliable in that regard.

I also saw that the Gaon shlit”a wrote:
“the current method of production involves breaking part of the shell and cutting off a small piece from the living creature. They claim that similar findings were discovered in ancient archaeological excavations. However, the Gemara is explicit that aside from the prohibition of trapping (Tzeida), there is no issur in wounding the Chilazon (Ptziyas Chilazon) or in extracting the dye (Netilas HaTzeva). The way they are doing it now, however, is akin to shearing a living animal, which according to all opinions is a Torah prohibition on Shabbos, similar to removing the foreskin from a living creature. This would make one liable either for taking a life (Netilas Neshama) or for shearing (Gozez), as explained by the Shita Mekubetzes (לפי”ד הש”מ ?) in Kesuvos. Therefore, it is clear that the current method does not align with the way Techeiles was traditionally produced.”

But this isn’t necessarily a raayah (proof) that this is how it was done in the time of Chazal — because there are multiple ways to extract the fluid. For example, one could puncture the shell and let the dye flow out, or smash the whole snail — shell and all — using a heavy hammer. Aristotle himself clearly writes that in ancient times, there were different methods for extracting the dye. So the archaeological findings mentioned as proof are hard to understand — because Murex shells have been found in various states. In some digs, they were opened in a way that suggests partial removal of the snail. In others, they were smashed completely. So there’s no conclusive evidence that only one method was used for obtaining the dye.

As for the essence of the objection — even if we were to grant, for argument’s sake, that they did indeed extract the dye in this way back then — we could still show that there is no Torah-level prohibition here, neither for netilas neshama nor for gozez.

Not netilas neshama, because the Rishonim — such as the Ritva in Shabbos 75a quoting his rebbi in the name of the Ramban, and the chiddushim attributed to the RaN there on daf 107a, as well as the Ra’avyah (Shabbos, Siman 194, p. 632) — all write that there is no liability for taking the life of a chilazon unless it is actually killed. This is because the creature is considered guf atum (a sealed body — meaning its internal systems are not exposed in the usual way). One might ask: But the Rishonim only said this to answer Tosafos’ question on Shabbos 75a (“Why isn’t one liable for netilas neshama when taking the blood?”), and if you go with Rabbeinu Tam’s answer — that the blood is mifkad pakid (loosely contained and not absorbed) — then the Ramban’s answer is unnecessary. So maybe this whole reasoning doesn’t apply to the Murex.

But that’s not correct. Clearly, the Ramban and the other Rishonim saw their approach as a strong and logical explanation to resolve the sugya. So there’s no reason not to use this same sevara (reasoning) to respond to Rav Miller’s objection — assuming the objection was factually valid to begin with, which we’ve already shown it likely isn’t.

As for gozez, that too doesn’t seem to apply here. The Shitah Mekubetzes’ chidush — that removing a piece of flesh from a living being counts as gozez — is only said in the context of milah (circumcision), where there is an explicit mitzvah to remove the orlah, which is considered a superfluous part of the body. But when it comes to other kinds of cutting, the Acharonim reject applying gozez. The Avnei Nezer (O.C. 131) and the Chasam Sofer (Shabbos 106b, s.v. tani) both write that even according to the Shitah Mekubetzes, gozez doesn’t apply to removing flesh unless it’s in the case of milah. Since there’s no tzivui (commandment) to remove other parts of the body, they’re not considered like hair or nails. Similarly, the Minchas Chinuch (in Mussach HaShabbos, Melachas Gozez, os 8) writes this explicitly.

I also saw that the Gaon shlit”a raised the following difficulty, quoting as follows:

“Furthermore, the Gemara indicates that the manner of Ptziya results in the taking of life, albeit unintentionally, which would be categorized as a destructive act or  Psik Reisha deLo Nicha Lei (an inevitable but unintended consequence) in relation to Netilas Neshama. According to their own admissions, the dye they produce is effective even after an hour or two following the organism’s death, which also suggests that this is not the same Techeiles mentioned in the Gemara.”

Now, the Gaon shlit”a attributes this information only to “their own words.” In my own conversation with him, he clarified that this knowledge was based solely on what they said. When I inquired and investigated this matter with members of the Ptil Tekhelet organization and pressed them for the source of this claim, it became clear that the researcher who had stated that the dye remains stable and usable for up to two hours after death said so only as a sevara — a logical assumption — without actually testing or verifying it experimentally. Nevertheless, this assumption was written up in the publications of the Ptil Tekhelet organization as if it were an established fact. If so, there’s no basis to raise a challenge based on this claim.

[And perhaps we can add further: There’s actually no clear raayah from the Gemara itself that the dye immediately begins to deteriorate upon extraction. The text doesn’t explicitly state that the blood or fluid spoils right away. It’s entirely possible that it remains usable for up to two hours. Even so, it would still be considered a pesik reisha d’lo nicha lei — an inevitable outcome that the person doesn’t want — since ideally, one would prefer that the fluid remains viable even longer. The death of the creature forces one to work quickly to extract the dye, especially when several snails are being processed at once — which takes time. In truth, the Gemara itself indicates that dyeing is possible even with a dead chilazon, as it says there: “R’ Yochanan said, when it was wounded — and it was dead.”]

The teshuvah of the Gaon shlit”a also states as follows:

“there is a ha’ara from the Teshuva of R’ Avraham ben HaRambam in Birkas Avraham, who reconciles his father’s (the Rambam’s) opinion that one who wounds or milks (Chovel v’Cholev) is chayav for threshing (Dash), even though Dash generally applies only to items that grow from the ground (Gedulei Karka – (בגדו”ק ומה”ט) ). For this reason, there is no liability of Disha with the Chilazon, as explained in the Gemara. He clarifies that true Dash requires the condition of growing from the ground, but the derivative forms (Toldos) of Disha do not. It seems that extracting the secretion from the Chilazon is not true Disha, but may at most be a Toldah of Dash, which according to the Rambam does not require the condition of growing from the ground.”

Now, it’s unclear what the Gaon shlit”a finds problematic with the Murex process, more than what Rashi himself says on Shabbos 75a — that pitzah (wounding the chilazon) means “pressing it by hand so that its blood comes out.” Rashi too holds it’s a toldah of dash, so if there’s a difficulty in applying dash to Murex, it would equally apply to Rashi’s view. In that case, R’ Avraham ben HaRambam’s words would be just as hard to reconcile with Rashi.

But in truth, the Murex aligns well with R’ Avraham ben HaRambam’s view. It’s very plausible that he understood pitzah to mean removing the shell from the body — unlike Rashi — and that this act is a classic case of dash, very similar to threshing grain from husks. This is supported by his language in Birkat Avraham (Siman 19), where he describes pitzah as “crushing and cutting, like one cracks open nuts.” And pitzas egozim (cracking nuts) refers to breaking the shell in order to extract the nut — as we see in Beitzah 34a and Rashi there.

Rashi, who did not explain it this way, likely wasn’t denying the existence of a shell on the chilazon. The Eglei Tal (Melachas Dash, se’if katan 7, os 25–26) explains that according to Rashi, even if the chilazon has a shell — or as the Eglei Tal puts it, a “bowl-like covering” — there would be no liability for dash in removing it, only in extracting the dye itself. That’s because when something is covered by two layers, dash only applies to removing the innermost one, the one that exposes the actual substance. But R’ Avraham ben HaRambam may follow the view of Rav Hai Gaon and Rabbeinu Chananel, brought by the Eglei Tal, who hold that there is dash liability on each layer removed. In that case, removing the Murex shell would indeed qualify as dash, and everything fits smoothly.

I also saw that the Gaon shlit”a raised an issue regarding the number of techeiles threads: since the Rishonim dispute how many to use, doing more than half a string of techeiles could potentially violate bal tosif (adding to the mitzvah), according to the Rambam. Without delving into the broader sugya of bal tosif, the very question seems puzzling. Let’s assume for a moment that we do have valid techeiles today — how can one argue that more than half a string shouldn’t be used due to bal tosif? What’s the alternative? Tie only half a string?

Following that logic, we should be more concerned about bal tigra (subtracting), according to other Rishonim — meaning we shouldn’t tie techeiles at all? That would itself be a concern of bal tigra, as the Beis HaLevi points out (vol. 1, Siman 42), not to mention the bitul asei (neglect of a positive mitzvah) of techeiles according to all opinions.

In truth, there are other solid reasons why there’s no halachic concern here for bal tosif or bal tigra. For a thorough treatment of this topic, see the end of the kuntres Chosam Shel Zahav, which addresses it at length.

He further writes the following:

“I have also seen that one of the supporters of the new Techeiles dismissed the words of the (גר”ח) Gra”Ch (R’ Chaim Soloveichik) ZT”L, who posited that based on the principle of Safek Deoraisa Lechumra (doubt in Torah law requiring a stringent approach), there is no chiyuv to do something that is a safek mitzvah…R’ Chaim’s reasoning applies to a mitzvah that one is obligated to fulfill with certainty, and there is a way to fulfill it in a doubtful manner. Even after fulfilling it out of doubt, the obligation to fulfill the mitzvah remains due to the principle of Safek Deoraisa Lechumra. Thus, there is no chiyuv from the Torah (מה”ת) to perform an act when the obligation to fulfill the mitzvah still remains after its performance…the ikkar of this svara is yashar and cannot be easily dismissed.”

With all due respect, these are very strange words, and they lack any real logic or halachic grounding. Practically speaking, a person has the opportunity — even amid doubt — to potentially fulfill the will of Hashem. What difference does it make if the doubt remains in his mind afterward? There is no known statement of Rav Chaim Brisker to this effect — not in his writings, not in the writings of his talmidim, and not in the name of his illustrious descendants. Without question, some misguided talmid mistakenly attributed this far-fetched idea to Rav Chaim.

And let’s be honest: no Torah-observant Jew would rely on such reasoning in any other area of mitzvah observance. Imagine someone stranded in the middle of nowhere — say, rural Russia or Africa — during Sukkos, and he comes across an esrog that might be grafted, or has some other safek pesul. Would any G-d-fearing Jew suggest that there’s no need to make any effort to use that esrog, simply because — as they claim in Rav Chaim’s name — there’s no obligation, since the doubt won’t be resolved in his mind even after using it?

This reasoning goes against the clear consensus of the poskim throughout the generations, who write explicitly that the principle of safek de’oraysa lechumra applies even when the chiyuv (obligation) is certain, and only the kiyum (fulfillment) is in doubt.

I won’t delve into the full breadth of the sugya here, but I will cite a number of major sources that directly address this matter:

• Shu”t Chasam Sofer (Kama, Siman 4)

• R’ Akiva Eiger’s glosses on Shulchan Aruch O.C. 688 (in Magen Avraham, se’if katan 4)

• Pri Megadim, Mishbetzos Zahav O.C. 36:6

• Shulchan Aruch HaRav O.C. 39:11 and 194:3

• Bikkurei Yaakov O.C. 688:53

• Mishnah Berurah O.C. 39:26 and 194:13, as well as Sha’ar HaTziyun there, citing numerous Acharonim

• Biur Halacha to O.C. 688:21

• Igros Moshe Y.D. Vol. 1, Siman 163, p. 328

These all demonstrate that the rule of safek de’oraysa lechumra obligates action even when the fulfillment is uncertain — and certainly doesn’t exempt a person from acting altogether based on speculative logic about inner doubt.

He further writes:
“As for the claim that Murex shells were found in archaeological digs, it is very likely that they were used for producing Argaman (purple dye), which until 24 years ago was not known to have a process to change its color to Kala Ilan. If so, it is plausible that in ancient times they were unaware of this method and instead produced a different color.”

But the reason no one knew until 24 years ago how to produce techeiles from the Murex was simply because they hadn’t really tried. Most experimentation took place in labs, under artificial conditions. In fact, the truth is that already back in 1884 there were researchers who discovered how to produce blue dye from Murex, but for whatever reason, their findings didn’t become widely known. Today we see it’s actually a very simple process — and there’s little doubt that it was known in ancient times. All one needs to do is dye outdoors so that sunlight reaches the material. It doesn’t even require direct sunlight — just some ultraviolet light for a few hours. If exposed to full sunlight, even a few minutes suffice. However, the older method, which didn’t expose the vat to sunlight and relied on only a few minutes of immersion, wouldn’t work to produce techeiles. So it’s necessary to conclude that they were using Murex to produce blue dye already back then.

I personally watched a video of a British researcher demonstrating the traditional Murex dyeing method. His process took ten days, and he covered the vat the entire time. He even said that if the dye were left uncovered, it would turn blue — but he wanted purple. From this we see the opposite: special care is needed to prevent the dye from becoming techeiles!

In addition, ancient texts clearly state that techeiles was produced from the Murex. One example is the legal code from the time of the Gemara — the laws of Emperor Justinian — which bans private citizens from producing dye from the Murex. That law lists various shades that were prohibited, and one of them is hyacinthina — which, in the Septuagint, is the Greek translation of techeiles.

Moreover, an ancient cloth dyed blue was found in a cave near the Dead Sea. It was tested and found to contain the same chemical components as Murex trunculus.

He also wrote:
“The Ben Ish Chai in his sefer Ben Yehoyada on Bava Metzia 61a writes, based on the kabbolah of the Ari Z”L, that the color of Kala Ilan has a shaychus to the Sitra Achra (forces of impurity), while kosher Techeiles does not. He elaborates on this at length, and if this is so, in my opinion, if this is indeed Kala Ilan, there is a significant concern al pi Kabbalah to avoid using this color, which is associated with the Sitra Achra.”

(a) The Sefer HaKaneh explains that the sitra achra’s hold on kala ilan is due to it being a plant-based product, growing from the ground.
(b) But the (פסקי הריא”ז) Piskei HaRia”z (R’ Yeshaya ben Elya di Torani) on Bava Metzia 61a explicitly permits dyeing tzitzis with kala ilan when authentic techeiles is not available.
(c) And it’s obvious that if someone puts in real effort to perform a mitzvah according to his understanding, he is not punished — on the contrary, he is richly rewarded. Chazal say in Kiddushin 81b: “If someone intended to eat non-kosher meat but ended up eating kosher, the Torah still requires atonement and forgiveness.” All the more so, when one tries to do a mitzvah — middah tovah merubah (Hashem’s attribute of kindness is even greater than His strictness).

He further wrote:
“besides this, from a halachic standpoint, it does not match the color of the corner of the garment. If it is not genuine Techeiles, then we require, lechatchila, that the tzitzis be the same color as the corner of the garment, which is why we only use white strings, as the Rema writes in Siman 9:5, even for garments of other colors. This is also why we are careful to make the tallis white, so that the tzitzis can also be white.”

(a) This claim is difficult to understand. The Mechaber himself writes that some are particular to make the tzitzis match the garment, but the Rema rules leniently — that one may use white strings even with a colored garment. The halacha follows the Rema, and the practice to make the tallis white is only a chumrah, not an obligation. How can a chumrah like that come to override a complete mitzvah like techeiles — or even a safek de’oraysa (Torah-level doubt) of techeiles?

(b) Moreover, many poskim write that the halacha of matching the tzitzis to the garment only applies to the white strings when techeiles is also present. But if techeiles is absent, there is no requirement at all for the strings to match the garment color. The Chazon Ish (O.C. 3:10) writes explicitly that only when one has four white and four techeiles strings does color matter — otherwise, if all are white, there is no restriction. A proof to this is from the Gemara, which discusses if “white alone is valid,” and brings no objection from garments of other colors. The Chazon Ish and other poskim conclude that there is no issue of color when there is no techeiles present.

The Aretz HaChaim (O.C. 9:5) rules this way as well, and the Mishnah Berurah (9:10) paskens like him.

He further writes:
“To sum up, the reason the proponents of the new Techeiles push this claim is due to the lack of another known species that fits the description, leading them to conclude that it must be the Murex. However, this reasoning is not convincing to those who are well-versed in these matters, as new discoveries are frequently made, especially in regard to the Chilazon, which Chazal already noted is not commonly found in our times.”

In truth, the Murex is found in the Mediterranean Sea — and for many years now, no new mollusk species have been discovered in that region. New species are only found in much deeper oceans, not in the habitat described in Chazal. And as I already wrote earlier in this essay, the identification of the Murex is based on the testimony of many Acharonim — including the Shiltei Giborim citing R’ Ezariah the doctor, the Musaf HaAruch, the Chavos Yair, the Yaavetz, R’ S.R. Hirsch, and the Tiferes Re’em — along with many other strong and compelling proofs beyond just the fact that no better candidate exists, which I don’t have space to elaborate on here.

As for the claim that Chazal said the chilazon no longer exists — I don’t know of any source for that. On the contrary, the Rambam (Hilchos Tzitzis 2:2) explicitly writes that the chilazon still exists and is metzuyah (found). The Sefer Mitzvos Gadol (positive mitzvah 26) quotes this as well. The Mahari”l (Shu”t HaChadashos, Siman 5) infers from the SeMaG that it is possible for the use of techeiles to return in every generation. The Radbaz (Siman 6825) also writes:
“It’s possible that the chilazon still exists today, but we don’t recognize it — or we don’t know how to trap it.”

And at the end of the letter, he concludes:
“In conclusion, based on the information available, there is strong reason to be stringent and refrain from using the new Techeiles that comes from the Murex.”

I will end my comments with the words of the Yeshuos Malko (end of Siman 1), who wrote regarding the techeiles of the Radzyner Rebbe:

“However, to enter into arguments and disputes we have no interest — for white tzitzis are kosher even when they are dyed, as is implied from Menachos 40a.”

May the reader accept the truth from whoever says it — not because of who said it, but because it is true. As Chazal said (Bamidbar Rabbah, Naso 14:4):
“How do we know that if someone hears a teaching from the mouth of even the simplest Jew, he should treat it as if it came from a great Sage? Not just as if from a Sage — but from the Sages. Not just from the Sages — but as if from the Sanhedrin. And not just the Sanhedrin — but as if it came from Moshe Rabbeinu. And not even Moshe — but as if from Hashem Himself.”