And they shall come back here: they refers to the descendants of Abram mentioned in verses 13-14. In translation it will often be necessary to make this clear by saying, for example, “Your descendants shall come back here.” Back here means to return to Canaan, the land God has promised to give them.

In the fourth generatio: generation translates Hebrew dor, which is used in the limited sense of a biological generation as well as in the general sense of a span of time. Some interpreters assume that in the patriarchal age a generation could be taken to be equivalent to a hundred years, and so four generations would mean four hundred years. Speiser argues for the sense of a time span, but nearly all translations, ancient and modern, prefer the term “generation.”

For the iniquity of the Amorites is not yet complete: this clause suggests a reason for God’s action against the Amorites that is not explained in detail but must be stated explicitly in translation to make it clear. The sense is that the Amorites are evil, but their sin has not yet reached the point where God has decided to drive them out of the land. The nature of the wickedness of the Canaanites is described in Lev 18; see particularly verses 24-28. Good News Translation provides a model that places God’s action at the beginning and end, “because I will not drive out the Amorites until they become so wicked that they must be punished.” Various translations use different expressions to convey the idea of iniquity becoming complete; for example, “because the bad behavior of the Amorite people who live here now has not reached its full mark yet” and “This will happen when the Amorite people who live here now have become really bad; when they become really bad, I will punish them and I will bring back….”

In 10.16 the term Amorites refers to one particular group of people. However, this name applies more generally in other references, as here, to all the people who occupied the mountain range of central Canaan. See comments on 10.16.

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 .