Cosmas Indicopleustes

This is the first heaven, shaped like a vaulted chamber, which was created on the first day along with the earth, and of it Isaiah speaks thus: He that hath established the heaven as a vaulted chamber. But the heaven, which is bound to the first at the middle, is that which was created on the second day, to which Isaiah refers when he says: And having stretched it out as a tent to dwell in. David also says concerning it: Stretching out the heaven as a curtain, and indicating it still more clearly he says: Who layeth the beams of his chambers in the waters.