This verse is parallel to the announcement of the flood in 6.17. Here the announcement has three parts: the rain will begin after seven days, the rain will last for forty days, and every living thing will be destroyed.

For in seven days: the seven days in this verse is the same week referred to in verse 10. For translates a Hebrew particle that may be understood here as introducing the reason for the commands given in verses 2-3, although many translations do not make this kind of connection. In seven days means “after seven days have passed,” “after seven days,” or “at the end of seven days.” Some languages have idiomatic expressions for time intervals like this; for example, “Seven days finished, I will…” and “One week remains, then I will….”

I will send rain upon the earth: send rain translates the causative form of the verb meaning to rain: “I will cause it to rain,” “I will make it rain.” Upon the earth is commonly added in such expressions; see, for example, 1 Kgs 8.36 “upon the land” and 17.14 “upon the earth.” This expression is often not translated in English and other languages in order to give a more natural style.

Forty days and forty nights: the forty days and forty nights used in this verse are the same as the ones referred to in verses 12 and 17. The sense is that the rain, which will begin after seven days, will fall continuously for forty days. The expression emphasizes the continuity of the rain, which may be expressed as “day and night for forty days” or “I will make it rain without stopping for forty days and nights.”

And every living thing that I have made I will blot out from the face of the ground: the relationship of this to the first part of the verse is that of result to cause. Accordingly it may be better with Good News Translation to show this relationship by “in order to” or “so that.” However, in some languages the order of the clauses naturally suggests a cause-and-effect connection without the need for such connecting expressions. A different way of expressing the relationship is used in one recent translation: “By means of this rain I will completely finish everything that lives….”

Every living thing is a rare word that occurs only here, in verse 23, and in Deut 11.6. Its meaning is parallel to “living beings” as used in 1.20. Blot out, meaning to “erase,” “destroy,” “wipe out,” is the same verb used in 6.7. From the face of the ground is the same as used in 2.6 and 6.7. See there for comments.

Quoted with permission from Reyburn, William D. and Fry, Euan McG. A Handbook on Genesis. (UBS Helps for Translators). New York: UBS, 1997. For this and other handbooks for translators see here .