Galatians 4:23
he, who was of the bond-woman, was born according to the ordinary course of nature; but he, who was of the free-woman, was born by virtue of the promise.
Hebrews 11:11
'Twas likewise through faith that Sara, though barren, received the power of becoming pregnant, and was delivered of a child when she was past age, because she judged him faithful who had promised.
Romans 9:7-8
neither are they who are the race of Abraham, all children: but 'tis said, "in Isaac shall thy posterity be called."
Romans 4:18-21
he it was who against hope believed in hope, that he should become the father of many nations, according to what was told him, "so shall thy posterity be:"
Romans 10:8
what does it say "more? the word is nigh thee, let it be in thy mouth and in thy heart:" that is the word of faith which we preach.
Galatians 4:28-29
Now we, my brethren, as Isaac was, are the children of the promise.