God said to Noah and to his sons with him: “This is the sign that I am giving for all ages to come, of the covenant between me and you and every living creature with you: I set my bow in the clouds to serve as a sign of the covenant between me and the earth.” (Gen 9:1-13)
Jesus began to teach them that the Son of Man must suffer greatly and be rejected by the elders, the chief priests, and the scribes, and be killed, and rise after three days. (Mk 8:27-33)
https://bible.usccb.org/bible/readings/021623.cfm
A friend once commented, “Sometimes a rainbow is just a rainbow” . . . but then at other times a rainbow is so much more. The sign of the covenant: the Cross and the Rainbow.