ייִדישער מחשבֿה אויף תהילים 118:19

We must consider the words, “the heavens were opened” (Ezek. 1:1); they give the key to the understanding of the whole. The figure of opening, also that of opening the gates, occurs frequently in the books of the prophets: e.g., “Open ye the gates that the righteous nation may enter in” (Isa. 26:2); “He opened the doors of heaven” (Ps. lxx-viii. 23); “Lift them up, ye everlasting doors” (ibid. 24:9); “Open to me the gates of righteousness, I will go into them, and I will praise the Lord” (ibid. 118:19). There are many other instances of this kind.