Acts 7:5-8

5He did not give any of it to him for an inheritance, not even a foot of ground, yet God promised to give it to him as his possession, and to his descendants after him, even though Abraham as yet had no child.

6But God spoke as follows: ‘Your descendants will be foreigners in a foreign country, whose citizens will enslave them and mistreat them for four hundred years.

7But I will punish the nation they serve as slaves,’ said God, ‘and after these things they will come out of there and worship me in this place.’

8Then God gave Abraham the covenant of circumcision, and so he became the father of Isaac and circumcised him when he was eight days old, and Isaac became the father of Jacob, and Jacob of the twelve patriarchs.