Genesis 2:4

These are the geneses of the heavens and earth when they were created in the day that the Lord God made the earth and heavens.

THESE ARE THE GENERATIONS OF THE HEAVEN AND THE EARTH WHEN THEY WERE CREATED. Scripture now relates the account of the heaven and the earth as regards rain and growth after they had been created and put in proper order, that the heavens shall give their dew and rain, and the ground shall give her increase, these making possible the existence of all living beings. And in the word b’hibaram (when they were created) — [which could be read as if it were two words: b’hei baram] — Scripture alludes to what the Rabbis have said: “He created them with the letter hei” [which is the last of the four letters of the Tetragrammaton]. It is for this reason that Scripture until this point mentioned only the word Elokim. This is explained in the verse: For all these things hath My hand made;) of the Tetragrammaton is in the Cabala considered the yad hashem (the hand of G-d). See my Hebrew commentary, p. 32. and so did Job say, Who knoweth not among all these, that the hand of the Eternal hath wrought this? This being so, the expression, in the day that the Eternal G-d made, refers covertly to the word bereshith (in the beginning).

אלה תולדות השמים והארץ בהבראם. These are the plants and the living creatures which had been the potential derivatives of heaven and earth already at the time when heaven and earth were first created. The potential ability for heaven and earth to produce the inhabitants of their respective domains was inherent in their respective composition from the first moment of their existence. When the Torah, in its very first verse, wrote the words את השמים and את הארץ, this was already an allusion to the additional factors which had been created together with heaven and earth, i.e. their ability to produce their respective derivatives.

ביום עשות ה' אלוקים ארץ ושמים, this potential was translated into an actual only on the day when G’d completed עשות, i.e. arranged in detail how these derivatives were to function and where and when. This occurred after the six “days” of creative activity. Only when that stage had been reached was G’d referred to in the Torah by His full name, i.e. ה' אלוקים.

אלה תולדות השמים והארץ, the word אלה refers to the phenomena mentioned during the 6 “days” of creation. Even though we have been told that G’d created the universe, as is clear from the verbs ויברא and ויעש all referring to G’d Himself doing these things, so where did the derivatives, תולדות come from? The Torah means that indeed G’d had created all these, but He had employed intermediaries, i.e. heaven and earth to whom He had issued directives. In Bereshit Rabbah 12,7 we are told לכל יש תולדות, everything has derivatives. We know that heaven and earth have derivatives. Rain has derivatives as it says in Job 38,28 do you know who is the father of rain, do you know who sired dew? [The concept being described is that none of these phenomena created themselves but were the product of something preceding them. Hence all phenomena that we perceive are derivatives of heaven or earth, which alone had been created by G’d directly, without intermediaries. Ed.]
Rabbi Shimon ben Lakish said that pearls are derivatives of dew; he referred to the bedolach mentioned in verse 12 of our chapter. Basically, the message of our verse is that everything that does produce derivatives, offspring, is itself slated to die and to disintegrate. This fact is proof that it is a creature and not a creator. On the other hand, if a phenomenon in the universe does not produce derivatives, this is proof that the phenomenon is not mortal, not subject to dissolution but that we are faced with a Creator and not a creature. Rabbi Azaryah in the name of Rabbi added that Rabbi Shimon ben Lakish’s comment was directed toward heaven, i.e. seeing that G’d is eternal and not subject to disintegration He needs no derivatives, “offspring” in order to perpetuate Himself. Everything which is a visible phenomenon is a derivative of either heaven or earth, seeing that the Torah commenced with the words בראשית ברא אלוקים את השמים ואת הארץ “First, G’d created heaven and earth.”
בהבראם, on the very day G’d created the heaven it already began to produce derivatives . This is the meaning of the words: ביום עשות ה' אלוקים ארץ ושמים. This is a reference to the day on which G’d confirmed that heaven was to be the upper waters, rakia, and earth was to be the dry land, yabashah. Starting with that day, heaven and earth each produced derivatives, i.e. a process of evolution began, one that followed rules set by G’d. The meaning of the word ביום is that this occurred simultaneously, i.e. both heaven and …