Midrash su Esodo 26:8

And this is the offering which ye shall take of them: gold, silver, and brass; and blue and purple and scarlet, and fine linen, and goats’ hair; and rams’ skins dyed red, etc. (Exod. 25:3). The Holy One, blessed be He, said to them: Actually You do not bring your own possessions, but the spoils I gave you at the Red Sea, as it is said: The wings of the dove are covered with silver (Ps. 68:14). And blue and purple and scarlet (Exod. 26:8).⁷To be used for the curtain before the ark. Blue, for they were dipped into the blood, to symbolize the blood that the patriarchs had already prepared (i.e., the blood of circumcision). It was called scarlet (tola’at), because it is said: Fear not, thou worm (tola’at)⁸A reference to Jacob’s sworn enemy Esau. Tola’ath means both worm and scarlet dyed yarn. Jacob (Isa. 41:14). The rams’ skins are mentioned to because of the merit of Jacob, as it is said: And she put the skins of the kids of the goats upon his hands (Gen. 27:16). The Holy One, blessed be He, declared: The heavens and the heavens of the heavens cannot contain Me, yet I caused My Shekhinah to dwell within the skins of the kids of the goats.

This is the offering … and rams’ skins dyed red, and sealskins (Exod. 25:3). R. Judah and R. Nehemiah discussed this verse. R. Judah said: It was a large pure animal, with a single horn in its forehead and a skin of six different colors that roamed the desert.⁹The authorities were undecided as to whether it was a domesticated animal or a wild beast. See Shabbat 28b. They captured one of them and from its skin made a covering for the ark. R. Nehemiah contended that it was a miraculous creature He created for that precise moment, and that it disappeared immediately thereafter from earth. Why is it called orot tahashim (“sealskins,” lit. “skins of tahashim”)? Because the verse states: The length of each curtain shall be thirty cubits (Exod. 26:8). What known animal could supply enough skin for a curtain of thirty cubits? It must, indeed, have been a miraculous creation, which disappeared (immediately after it was created).