Genesis 15:16

Iniquity - Sin; wickedness; evil.

In the fourth generation - In former times most people counted by generations, to each of which was assigned a term of years amounting to 20, 25, 30, 33, 100, 108, or 110; for the generation was of various lengths among various people, at different times. It is probable that the fourth generation here means the same as the four hundred years in the preceding verse. Some think it refers to the time when Eleazar, the son of Aaron, the son of Amram, the son of Kohath, came out of Egypt, and divided the land of Canaan to Israel, Joshua 14:1. Others think the fourth generation of the Amorites is intended, because it is immediately added, The iniquity of the Amorites is not yet full; but in the fourth generation they should be expelled, and the descendants of Abram established in their place. From these words we learn that there is a certain pitch of iniquity to which nations may arrive before they are destroyed, and beyond which Divine justice does not permit them to pass.

In the fourth age. - An age here means the average period from the birth to the death of one man. This use of the word is proved by Numbers 32:13 - "He made them wander in the wilderness for forty years, until all the generation that had done evil in the sight of the Lord was consumed." This age or generation ran parallel with the life of Moses, and therefore consisted of one hundred and twenty years. Joseph lived one hundred and ten years. Four such generations amount to four hundred and eighty or four hundred and forty years. From the birth of Isaac to the return to the land of promise was an interval of four hundred and forty years. Isaac, Levi, Amram, and Eleazar may represent the four ages.

For the iniquity of the Amorite is not yet full. - From this simple sentence we have much to learn. First. The Lord foreknows the moral character of people. Second. In his providence he administers the affairs of nations on the principle of moral rectitude. Third. Nations are spared until their iniquity is full. Fourth. They are then cut off in retributive justice. Fifth. The Amorite was to be the chief nation extirpated for its iniquity on the return of the seed of Abram. Accordingly, we find the Amorites occupying by conquest the country east of the Jordan, from the Arnon to Mount Hermon, under their two kings, Sihon and Og Numbers 21:21-35. On the west of Jordan we have already met them at En-gedi and Hebron, and they dwelt in the mountains of Judah and Ephraim Numbers 13:29, whence they seem to have crossed the Jordan for conquest Numbers 21:26. Thus had they of all the tribes that overspread the land by far the largest extent of territory. And they seem to have been extinguished as a nation by the invasion of Israel, as we hear no more of them in the subsequent history of the country.

15:16 They shall come hither again - Hither to the land of Canaan, wherein thou now art. The reason why they must not have the land of promise in possession till the fourth generation, is because the iniquity of the Amorites was not yet full. The righteous God has determined, that they shall not be cut off till they are arrived to such a pitch of wickedness; and therefore till it come to that, the seed of Abram must be kept out of possession.