Acts 7:8

7:8 Then 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.

Acts 16:3

16:3 Paul wanted Timothy to accompany him, and he took him and circumcised him because of the Jews who were in those places, for they all knew that his father was Greek.