Cross reference
Genesis 21:5
5 Now Abraham was a hundred years old when the birth of Isaac took place.
Genesis 17:17
17 Then Abraham went down on his face, and laughing, said in his heart, May a man a hundred years old have a child? will Sarah, at ninety years old, give birth?
Genesis 17:1
1 When Abram was ninety-nine years old, the Lord came to him, and said, I am God, Ruler of all; go in my ways and be upright in all things,
Romans 4:19
19 And not being feeble in faith though his body seemed to him little better than dead (he being about a hundred years old) and Sarah was no longer able to have children: