It is important to realize in this regard that Genesis (for all its importance) is really only the prologue to the exodus and the establishment of Israel as a nation in covenant with Yahweh. Genesis is, in effect, the prologue of the Pentateuch. The implied reader or listener would understand Genesis, therefore, through the prism of Israelite cultural knowledge, prominent within which would be the idea of Israel’s election and Israelite religious tradition and practice.
The implication of the existence of such cultural presuppositions in the mind of the implied reader is that the implied reader would approach the creation account in Gen 1:1–2:3 with a knowledge of the weekly pattern of six days’ work and one day’s rest as part of their cultural “baggage.” This means that the concept of God working to order and fill the world over six days, then resting on the seventh when everything was complete, would most naturally have been understood by the implied reader in terms of a cycle of normal 24-hour days, on analogy with the Hebrew custom of six day’s work, one day’s rest.
The initial impression that the implied reader would have received on reading or hearing the creation account is that God’s activity fits our own pattern of activity. We work for six days and then enjoy our Sabbath rest, and so does God! But it is not a case of God imitating the Hebrews. Further reflection would involve the application of the truth of the fourth commandment to the creation narrative:
Remember the Sabbath day, to keep it holy. Six days you shall labor, and do all your work, but the seventh day is a Sabbath to Yahweh your God. On it you shall not do any work, you, or your son, or your daughter, your male servant, or your female servant, or your livestock, or the sojourner who is within your gates. For in six days Yahweh made heaven and earth, the sea, and all that is in them, and rested on the seventh day. Therefore Yahweh blessed the Sabbath day and made it holy (Exod 20:8–11).Knowledge of the fourth commandment and the Hebrew custom of resting from one’s work on the seventh day would effectively function as a hermeneutical guide for the the way in which Gen 1:1–2:3 would be understood. Hence the conclusion: it is not a case of God imitating us, but us imitating God! We Israelites work for six days and rest on the seventh, because that is what God did.
In this way the implied reader would come away from his or her reading of Gen 1:1–2:3, not only with an assumption that the days of the creation week were normal 24-hour days, on analogy with one’s own experience of work and rest; but more importantly, with the knowledge that God himself is the analogue for human work and rest. This idea has important ramifications for how the creation mandate of Gen 1:28 is to be understood.