12 As the sun was setting, Abram fell into a deep sleep, and a thick and dreadful darkness came over him. 13 Then the Lord said to him, “Know for certain that for four hundred years your descendants will be strangers in a country not their own and that they will be enslaved and mistreated there. 14 But I will punish the nation they serve as slaves, and afterward they will come out with great possessions. 15 You, however, will go to your ancestors in peace and be buried at a good old age. 16 In the fourth generation your descendants will come back here, for the sin of the Amorites has not yet reached its full measure.”
17 When the sun had set and darkness had fallen, a smoking firepot with a blazing torch appeared and passed between the pieces. 18 On that day the Lord made a covenant with Abram and said, “To your descendants I give this land, from the Wadi of Egypt to the great river, the Euphrates— 19 the land of the Kenites, Kenizzites, Kadmonites, 20 Hittites, Perizzites, Rephaites, 21 Amorites, Canaanites, Girgashites and Jebusites.” Genesis 15:12-21
The Lord reiterated something He had been promising all along, that Abram would have descendants. Right now even though he believed God, he had no children. So the Lord was promising a lot of children. And now He gave them the bad news, that they would be enslaved by the Egyptians and treated harshly for 400 years. Four hundred years seemed to be the penalty for the sins of the Amorites/Canaanites.
They would come out with great possessions but they would certainly have to “pay it forward”, so to speak.
Leviticus 18 spells out the sins of the Canaanites, and they were quite evil.
If you’ve followed this site for any length of time, you’ll recall the Russian proverb I use a lot, “God sees everything but waits.” This applies to the Canaanites. It applies to us. It also applies to the evil we see around us, especially when we see people getting away with murder, so to speak. Everyone will be accountable for what they do. No one will escape judgement.