Thy seed shall be strangers So they were in Canaan first, Psalms 105:12, and afterward in Egypt: before they were lords of their own land, they were strangers in a strange land. The inconveniences of an unsettled state make a happy settlement the more welcome. Thus the heirs of heaven are first strangers on earth. And they shall serve them So they did the Egyptians, Exodus 1:13. See how that which was the doom of the Canaanites, Genesis 9:25, proves the distress of Abram's seed: they are made to serve; but with this difference, the Canaanites serve under a curse, the Hebrews under a blessing. And they shall afflict them See Exodus 1:11. Those that are blessed and beloved of God are often afflicted by wicked men. This persecution began with mocking, when Ishmael, the son of an Egyptian, persecuted Isaac, (Genesis 21:9,) and it came at last to murder, the basest of murders, that of their new-born children; so that, more or less, it continued four hundred years.
Related Commentaries of Genesis 15:13
Genesis 15:13
13 And he said unto Abram, Know of a surety that thy seed shall be a stranger in a land that is not theirs, and shall serve them; and they shall afflict them four hundred years;