Coke's Commentary on the Holy Bible
Genesis 9:14
When I bring a cloud—the bow shall be seen in the cloud— It is not meant here, that the bow shall be always seen, but at certain times, often enough to put men in mind of the promise, and to stir up their belief of it. And when it is said, Genesis 9:16. I will look upon it, that I may remember, it is easy to observe, that this is spoken only after the manner of men: He, who cannot forget, needs no token or sign to put him in mind of his promise. This sign was for the comfort of man, not for the admonition of God: the meaning therefore is, that men might consider this bow as a signification that God had obliged himself to this promise, and would certainly fulfil it. The opinions of expositors have been much divided, respecting the original of this sign. Bishop Warburton, whose opinion in this instance I conceive to be just, observes, "The bow was not then first set in the clouds, but then FIRST set as a token." In the case before us, the most novel, or most supernatural, appearance could add nothing to their assurance arising from the evidence of God's veracity. As, on the contrary, had the children of Noah been ignorant of that attribute of the Deity, such a phaenomenon could have given no assurance at all. For what then served the rainbow? For the wise purpose so well expressed by the sacred writer, for the token of the covenant; that is, for a memorial or remembrance of it throughout all generations.
The heathens, I doubt not, borrowed many of their fables from this sacred record concerning the rainbow. Homer says, Il. Genesis 11:28. that Jupiter established the rainbow, τερας μεροπων ανθρωπων, "a sign to man amidst the skies." And very probably, from some tradition of this original covenant, the ancient poets feigned Iris, or the rainbow, to be the daughter of Wonder, θαυμαντος, and the messenger of Jupiter and Juno, the heaven, or air and clouds.
REFLECTIONS.—The covenant is now signed and sealed by a visible token, the rainbow; a glorious object, and a constant assurance of God's remembrance of us, and of our security from the descending waters. Observe, 1. As we are apt to be affected with visible objects; God therefore, not only in the covenant of nature, but of grace, hath instituted visible signs for our greater comfort and confidence. 2. The cause of the bow in the clouds, is the refraction of the beams of the sun. Jesus, the Sun of Righteousness, sits with the rainbow round about his throne, and therefore his people are safe from fear of evil. 3. The sign of our security in the cloud, should ever awaken our thankfulness, and lead up our minds from temporal promises thus fulfilled, to conclude the certainty of the eternal promises, which are yet in hope.