Cross reference
Genesis 17:24
24 And Abraham was ninety years old and nine, when he was circumcised in the flesh of his foreskin.
Romans 4:11
11 and he received the sign of circumcision, a seal of the righteousness of the faith which he had while he was in uncircumcision; that he might be the father of all them that believe, though they be in uncircumcision, that righteousness might be reckoned unto them;
Genesis 12:4
4 So Abram went, as Jehovah had spoken unto him; and Lot went with him: and Abram was seventy and five years old when he departed out of Haran.
Genesis 17:1
1 And when Abram was ninety years old and nine, Jehovah appeared to Abram, and said unto him, I am God Almighty; walk before me, and be thou perfect.
Genesis 17:17
17 Then Abraham fell upon his face, and laughed, and said in his heart, Shall a child be born unto him that is a hundred years old? and shall Sarah, that is ninety years old, bear?
Romans 4:19-20
19 And without being weakened in faith he considered his own body now as good as dead (he being about a hundred years old), and the deadness of Sarah's womb;
20 yet, looking unto the promise of God, he wavered not through unbelief, but waxed strong through faith, giving glory to God,