In fact, the creation account contains chiastic structures within chiastic structures. If the creation account is not poetry, nothing is!
The general construction of the creation account is set up like this:
A “He [God] created” (1:1b) [Reading the Hebrew, "he created" comes before "God", which makes little sense in English, so it's switched in English.]
B “God” (1:1b)
C “heavens and earth” (1:1b)
X FORMING AND FILLING OF THE EARTH (1:2-31)
C’ “heavens and earth” (2:1)
B’ “God” (2:2)
A’ “He [God] had made” (2:3)
Then, Genesis 2:4 makes a great conclusion:
A “heaven”
B “earth”
C “created”
C’ “made”
B’ “earth”
A’ “heaven”
Not only this, but there are seven 7's in this passage. "7" is the number of perfection or completion:
7 paragraphs: The arrangement of Genesis 1:1—2:3 consists of an introduction and seven paragraphs. The introduction identifies the Creator and creation (Gen. 1:1-2); six paragraphs corresponds to the six creation days (1:3-21). The seventh paragraph marks the climactic seventh day, the day of consecration (2:1-3).
Seven announcements of commandments. "God said" occurs 10 times, but it's grouped into 7 groups: (Gen. 1:3; 6; 1:9; 1:11; 1:14, 1:20;
1:24; 1:26, 28, 29). (10 is the number of testimony, law, and responsibility.) [I have a comment to make on the 10 here and the 8 below, if anyone's interested.]
The order formula: “Let there be . . .”, while occurring eight times, the formula
is grouped into seven (Gen. 1:3; 1:6, 9; 1:11; 1:14; 1:20; 1:24; 1:26).
The fulfillment formula: “And it was so” occurs seven times (Gen. 1:3; 1:7; 1:9;
1:11; 1:15; 1:24; 1:30).
The execution formula: “And God made” occurs seven times (Gen. 1:4; 1:7;
1:12; 1:16; 1:21; 1:25; 1:27).
The approval formula: “God saw that it was good” occurs seven times (Gen.
1:4; 1:10; 1:12; 1:18; 1:21; 1:25; 1:31).
The subsequent divine word: God’s naming or blessing occurs seven times
(Gen. 1:5; 1:8; 1:10; 1:22; 1:28).
Seven days affirmed: There are seven days mentioned (Gen. 1:5; 1:8; 1:13;
1:19; 1:23; 1:31; 2:2).
Even day four is poetic:
A “to divide the day from the night” (1:14a)
B “for signs, for fixed times, for days and years” (1:14b)
C “to give light on the earth (1:15)
D “to rule the day” (1:16a)
D’ “to rule the night (1:16b)
C’ “to give light on the earth” (1:17)
B’ “to rule the day and the night” (1:18a)
A’ “to divide the light from the darkness” (1:18b)