▼9:13This reference to rainbows as arcs in the sky calls to mind the ark of Noah. And it calls to mind the subsequent ark of the Covenant, which held the tablets of the Ten Commandments. And it calls to mind the Virgin Mary, who is the ark of the New Covenant. She will appear in the sky, just as the Book of Revelation says, in the last days, as a further sign of the covenant between God and man.(Conte)