Ben Yehoyada – Sotah 46b on Luz

“It is Luz where they dye with techeiles” (Shoftim 1:26).

It appears that although the dye of techeiles comes from the blood of the chilazon, which is found in the portion of Zevulun, nonetheless, its color absorbs better in the atmosphere of Luz than if it were dyed in the air of another place. Therefore, they would go to Luz to dye the techeiles there.

However, this is difficult—what connection is there between this praise, that its air is good for dyeing techeiles, and the other praises mentioned about it, that it was spared from the sword of Sancheiriv, the sword of Nevuchadnetzar, and the sword of the Malach HaMaves?

And it appears to me, b’siyata d’shmaya, as explained in the words of our master, the Arizal in Shaar Maamarei Rashbi, that the color of techeiles repels the gaze and sight of the kelipos and the chitzonim.

And for this reason, when the Bnei Kehas would transport the Aron, the Shulchan, the Menorah, and the Golden Mizbeach in the midbar from place to place, they would first spread a techeiles garment over them from above. The reason is that the chitzonim wish to look upon the kodesh and take hold there, and when they prepare to gaze at them, the color of techeiles prevents them from taking hold in a place of kedusha (see there).

Thus, we find that the color of techeiles repels the kelipos and chitzonim, which are enemies from above. And therefore, this praise of Luz—that the color of techeiles absorbs well in its air, which repels the enemies from above—is mentioned together with the other praises, that it repelled enemies from below—Sancheiriv and Nevuchadnetzar, who were earthly enemies, as well as the Malach HaMaves, who is a spiritual enemy of the soul.