Luke 1:59
On the eighth day they came to circumcise the child, and they were going to name him Zechariah, after his father.
Luke 2:21
When he was eight days old and it was time to circumcise him, he was named Jesus, as the angel had named him, before his birth was first expected.
Philippians 3:5
I was circumcised when I was eight days old. I am a descendant of Israel. I belong to the tribe of Benjamin. I am a Hebrew, and the son of Hebrews. As to the Law, I was a Pharisee;
Acts 7:8
And he made the agreement of circumcision with him, and so Abraham became the father of Isaac and circumcised him on the eighth day, and Isaac became the father of Jacob, and Jacob of the twelve patriarchs.