23 but he indeed who was of the bondwoman, was born in the ordinary course of nature; and he who was of the freewoman, in virtue of the promise.
Galatians 4:23 Cross References - Thomson
Genesis 17:15-19
15 Moreover God said to Abraham, "Sara thy wife shall not be called Sara. Her name shall be Sarah.
16 And I will bless her and give thee a son by her. And I will bless him. And he shall become nations, and from him there shall be kings of nations."
17 Upon this Abraham fell on his face and smiled, and said in his heart, To him who is in his hundredth year shall a son be born? and shall Sarah bring forth in her ninetieth year?
18 And Abraham said to God, Let this Ismael live before thee.
19 Whereupon God said to Abraham, Nay, behold Sarah thy wife shall bear thee a son, and thou shalt call his name Isaak. And I will establish my covenant with him for an everlasting covenant to be his God and the God of his seed after him.
Genesis 18:10-14
10 Then he said, I will return and come to thee about this time twelve month, and Sarah thy wife will have a son. And Sarah heard, being at the door of the tent behind them.
11 [Now Abraham and Sarah were far advanced in life, and it had ceased to be with Sarah after the manner of women.]
12 And Sarah smiled within herself, saying, It hath never been so with me even to this time, and my lord is old.
13 And the Lord said to Abraham, Why did Sarah smile within herself, saying, Shall I indeed bring forth? I who am old?
14 Can any thing be impossible with God? About this time twelve month I will return to thee, and Sarah shall have a son.
Genesis 21:1-2
Romans 4:18-21
18 Against hope he believed with a hope that he should become father of many nations according to what was said, "So shall thy seed be"
19 and far from being weak in faith, he did not consider his own body now become dead, he being then in his hundredth year; nor the deadness of Sarah's womb.
20 He disputed not against the promise of God by unbelief; but was strong in faith, giving glory to God,
21 and being fully persuaded that he was able to perform what he had promised.
Romans 9:7-8
Romans 10:8
8 But what doth it say? The matter is near thee, in thy mouth and in thy heart. That is, the matter of this belief, which we proclaim,
Galatians 4:28-29
Hebrews 11:11
11 By faith Sarah also received strength for conception, and was delivered of a son when she was past age, because she judged him faithful who had promised.