The rainbow that appears in Lent

What do we learn from Noah, science and Jewish tradition?

What do you think when you see a rainbow?

“Good, the rain is over.”

“Oh, isn’t that beautiful?”

“There’s a scientific phenomenon of water and light.”

Do you also think about blessing God?

If you were Jewish, you might immediately say the following prayer:

“Blessed are you, Lord our God, king of the universe, who remembers the covenant, and is faithful to his covenant, and keeps his promise.”

What promise?

That would be the promise made to Noah that we hear about in the first reading for the First Sunday of Lent this year: “I will establish my covenant with you, that never again shall all creatures be destroyed by the waters of a flood; there shall not be another flood to devastate the earth” (Gn 9:11).

War Weapon

To mark that promise, God set “his bow in the heavens.” That, of course, means the rainbow. We all know that. But how many of us realize that “bow” also means the war weapon of the time: the bow with its arrows.

Jews, dating back to biblical times, understood that God had set aside his bow (its curve is seen in the rainbow) and his arrows (lightning) in the name of peace with humankind. A 19th- century rabbi, Samson Hirsch, noted that we should look at how the curve of the bow points away from us and realize it as a sign of peace. This is what a warrior does to show peace: turns his bow away from you.

In at least two other places in the Bible, the rainbow is mentioned as a weapon: Psalm 7:12-13 and by the prophet, Habbakuk (3:9).

Divine Presence

The rainbow does not appear often in the Bible, but when it does, it refers to the power of God. The better known references are from the prophet Ezekiel (1:27-28) and in the Book of Revelation (4:1-3 and 10:1), describing a rainbow running around the divine presence of God enthroned in heaven. The Book of Sirach also describes the rainbow in the sky: “It spans the heavens with its glory, the hand of God has stretched it out in power” (43:12).

A rainbow is defined by Merriam-Webster as “an arc or circle that exhibits, in concentric bands, the colors of the spectrum … formed opposite the sun by the refraction and reflection of the sun’s rays in raindrops, spray or mist.”

The many colors of a rainbow are made by the way sunlight is bent as it is reflected by the sphere of each raindrop. In 1637, the mathematician René Descartes determined that the different colors we see occur because “the paths of the rays fall on the different points of a globe of water” and bend the light at a specific angle. That angle, Descartes determined, is from 41 to 42 degrees — nothing more and nothing less. (There is also so much white light reflected from the raindrops that a lighter band makes the sky inside of the arc of a rainbow appear brighter.)

40-degree Angle

A rainbow results when light turns back on itself at roughly a 40-degree angle. During the 40 days of Lent, we are asked to turn back to the Lord with our whole heart (Ash Wednesday’s first reading, from Joel 2). Doing so can focus a greater reflection of the Gospel message into our hearts — and draw us closer to the God who makes covenants with us.

As Rabbi Shlomo Riskin, an American-born rabbi now living in Efrat, Israel, is often quoted as saying: “The rainbow is a half-picture, lacking a second half to complete the circle of wholeness. God can pledge not to destroy humanity, but since God created humanity with freedom of choice, God cannot guarantee that humanity will not destroy itself.

“This is to say,” the rabbi continued, “that God will take care of God’s part of the rainbow, but we have to do our part, to be God’s partners in caring for the world.”

Seeing a rainbow should remind us that God is there with us, and we are called to respond in praise, prayer and action.


Sources: “Easton’s Bible Dictionary”; “Smith’s Bible Dictionary”; biblestudy,org; “International Bible Study Encyclopedia”;;;; The National Center for Atmospheric Research and the University Corporation for Atmospheric Research at; and the National Jewish Outreach Program at