פּירוש אויף בראשית 1:17

And He placed - Do not be astonished over the word "and He placed," for it is also written, "My bow have I placed" (Genesis 9:13).

And God placed them in the firmament of the skies, etc.: He fixed them and fixed their laws, [so] that they should shine upon the earth.

And He placed, etc.: At the time of the act, the order was reversed from the time of the pronouncement - at first, they came into the firmament of the skies to shine upon the earth, and afterward to govern, and afterward to separate. And the reason [for this] is simple; that at the first instant that the Holy One, blessed be He, placed them in the firmament, they shined upon the earth, but they still did not act upon their rulership until they moved. And in their moving, they impacted upon the earth, and they still had not separated [anything] until the evening.