Exodus 26: Take Cover!

“And make for the tent a covering of tanned ram skins, and a covering of Tchashim skins above” (verse 14)וְעָשִׂיתָ מִכְסֶה לָאֹהֶל עֹרֹת אֵילִם מְאָדָּמִים וּמִכְסֵה עֹרֹת תְּחָשִׁים מִלְמָעְלָה (שמות כו:יד)Two questions from this verse. First, why does the goat hair cover need two more covers? The second is what does Tchashim mean? Tchashim is translated as fine leather in some places. Tachash also means an aquatic mammal—like a dolphin or seal. It is unclear where the Israelites would procure dolphin and seal skins in the middle of the wilderness. Unlike goats or rams, these animals would not be domesticated simply because there would be nowhere to keep them! Josephus describes tachash as skins “dyed blue,” from dye taken from sea mollusks indicating a technology to color ordinary leather, not actual exotic marine mammal skins. The Talmud in Shabbat 28b says the Tchashim were unique sungle horned creatures that appeared to Moshe in the wilderness for this specific purpose and then were never seen again. Marine mammals like dugongs and some dolphin species naturally inhabited the Red Sea and Gulf of Aqaba—within reach of the Israelites during the Sinai journey. Their hides could have been harvested directly by Israelite groups or obtained from Red Sea coastal areas. As to the first question, Rashi quotes the Gemara in Shabbat where the rabbis disagree whether there were two covers on top of the goats hair roof or there was one cover made of two materials. Rashi’s answer implies that this secondary covering was purely decorative. Haamek Davar explains that “above” does not mean that these skins were on top of the goats hair roof, but that they were above the Holy of Holies only. “Above” means above the holiest part. Ibn Ezra gives a practical reason. This extra covering was meant to protect the Mishkan from the rain. This reminds me of my father and brother who both have rolled up tarps ready to spread over the Sukkah when it rains to protect the decorations and lights inside. Unlike the tarp, this roof is on all the time. It’s possible that Ibn Ezra arrives at this answer due to the use of marine animal skins. These skins would be best suited to protect the tent from water.