4 This is the history of the heavens and the earth when they were created, in the day that the Lord God made the earth and the heavens,
5 before any plant of the field was in the earth and before any herb of the field had grown. For the Lord God had not caused it to rain on the earth, and there was no man to till the ground;
6 but a mist went up from the earth and watered the whole face of the ground.
Genesis 2 isn’t a separate account of creation, but an expanded account of the creation that took place on day 6. This makes sense if Adam wrote the portion beginning with v.4 (see next comment), as he would be primarily concerned with his own origins.
Morris believes, and it’s an interesting thought, that the words “This is the history” (v.4) or “These are the generations” in the KJV, record changes in authorship in the Bible. Morris believes that, since no man was around to observe or record until day 6, the first section was written by God Himself. Adam, then, would take over with verse 5. Whether that was the case, or whether instead the Holy Spirit revealed the early history of the world to Moses, doesn’t really matter. In either case, what we have is what the Lord wants us to have—His infallible Word.
“This is the account of” … is regularly used throughout Genesis to introduce major new narrative sections (see 5:1; 6:9; 10:1; 11:10, 27; 25:12, 19; 36:1; 37:2), and in which the word account—literally, “generations”—always refers, not to the history of that which is named in the title (in this case the heavens and earth—i.e., the sky and the land), but rather to the human generations(s) that come from that which is named in the title (in this case, therefore, Adam—who came from the land—and Eve, as well as their own children). — Wechsler, page 75.
The second half of v.4, therefore, begins the narrative proper, and, in a clear parallel to the opening of the general introduction to Creation in chapter 1, introduces a series of dependent (i.e., “background”) clauses intended to “set up” the main event—in this case, the creation of man in v.7. The purpose of these “background” clauses comprising vs. 4-6 is to underscore the perfection of the environment into which God is about to place man, not by reiterating what was included in pre-Fall Creation, but by telling us, from the opposite perspective, what was excluded from pre-Fall Creation. — Wechsler, page 76.
Consistent with both the grammar and context of the Hebrew text, the word “day” in v.4 refers to the sixth day of Creation, whereas the verb translated “were created” refers to what had already been done and accomplished by that sixth day. — Wechsler, page 76.
Lord God (v.4) — Prior to this the general name “God” (Elohim) has been used. In v.4 the name Jehovah (LORD) is used for the first time.
As to the expressions “shrub of the field” and “plant of the field,” these properly refer not to plants in general, but specifically to inutile, “troublesome” plants, such as thorns and thistles, that inhibit man’s easy access to the good vegetation he was given to eat from—which “troublesome” plants only entered Creation after the Fall, as we clearly see in the very next occurrence of the phrase “plants of the field,” in 3:18, where it is indeed paralleled (i.e., equated) with “thorns and thistles.” That the “good” vegetation created on the fourth day in 1:11-12 was indeed already present in 2:4-5 is also evident from the reference to the mist in v.6 that we are told would “water the whole surface of the land,” which would make little sense if there were no plants to be watered (in Scripture the expression “to water” is consistently used for plants and animals, not bare land).
Likewise indicative of what was excluded from pre-Fall Creation are the remaining two statements in v.5—to wit, that “the Lord God had not sent rain upon the earth,” which clearly alludes to the Flood, a post-Fall consequence of depravity, seeing that the next time that this specific phrase is used (and the first time that rain actually enters Creation) is in 7:4; and that there was no man to cultivate the ground, which statement—though seemingly neutral at first sight—likewise bears a specifically post-Flood consequence-of-depravity connotation, since the next time that we see this precise expression used is in 3:23, where it clearly refers to the “toil” and hard labor which came with the punishment for man’s sin. (This is not the same phrase used in 2:15.) — Wechsler, pages 76-77.
The original hydrologic cycle was drastically different from that of the present day. The present cycle, which began at the time of the great Flood, involves global and continental air mass movements, and annual and seasonal temperature changes. … This cycle centers around the solar evaporation of ocean waters, transportation to the continents in the atmospheric circulation, condensation and precipitation in the form of rain and snow, and transportation back to the ocean via rivers. in the original world, however, there was no rainfall on the earth. As originally created, the earth’s daily water supply came primarily from local evaporation and condensation. There was also, as noted later, a system of spring-fed rivers.
The inhibition of true rainfall was probably … accomplished by the great vapor canopy, “the waters above the firmament.” Maintaining and approximately uniform temperature worldwide, no great air mass movements were possible under the canopy, and the necessary conditions for rainfall unsatisfied. — Morris, pages 84-85.