Like the appearance of the bow that is in the cloud on the day of rain, so was the appearance of the brightness all around. Such was the appearance of the likeness of the glory of the LORD. And when I saw it, I fell on my face, and I heard the voice of one speaking.
The Prophet now adds, that the likeness of a celestial bow was presented to him, which profane men call his, and imagine that she performs the commands of the gods, and especially of Juno. But Scripture calls it the bow of God, not because it was created after the Deluge, as many falsely suppose, but because God wished to stir up our hope with that...
All the other parts of this vision were but a preface and introduction to this. God in them had made himself known as Lord of angels and supreme director of all the affairs of this lower world, whence it is easy to infer that whatever God by his prophets either promises or threatens to do he is able to effect it. Angels are his servants; men are his tools.
Commenting on Ezekiel 1:26-28
As the appearance of the bow that is in the cloud in the day of rain,.... The rainbow, which is no other than the reflection of the rays of the sun in a thin watery cloud on a rainy day: so was the appearance of the brightness round about it; so Christ is represented as clothed with a cloud, and a rainbow about his head...