Genesis 18...
1
And the Lord appeared unto him (Abraham) in the plains of Mamre:and he
sat in the tent door in the heat of the day; 2 And he lift up his eyes
and looked, and, lo, three men stood by him:and when he saw them, he ran
to meet them from the tent door, and bowed himself toward the ground,
3
And said, My Lord, if now I have found favour in thy sight, pass not
away, I pray thee, from thy servant:4 Let a little water, I pray you, be
fetched, and wash your feet, and rest yourselves under the tree:5 And I
will fetch a morsel of bread, and comfort ye your hearts; after that ye
shall pass on:for therefore are ye come to your servant.
And they said, So do, as thou hast said.
6
And Abraham hastened into the tent unto Sarah, and said, Make ready
quickly three measures of fine meal, knead it, and make cakes upon the
hearth. 7 And Abraham ran unto the herd, and fetcht a calf tender and
good, and gave it unto a young man; and he hasted to dress it. 8 And he
took butter, and milk, and the calf which he had dressed, and set it
before them; and he stood by them under the tree, and they did eat.
9 And they said unto him, Where is Sarah thy wife? And he said, Behold, in the tent.
10
And he said, I will certainly return unto thee according to the time of
life; and, lo, Sarah thy wife shall have a son. And Sarah heard it in
the tent door, which was behind him. 11 Now Abraham and Sarah were old
and well stricken in age; and it ceased to be with Sarah after the
manner of women. 12 Therefore Sarah laughed within herself, saying,
After I am waxed old shall I have pleasure, my lord being old also?
13 And the Lord said unto Abraham, Wherefore did Sarah laugh, saying, Shall I of a surety bear a child, which am old?
14 Is any thing too hard for the Lord?
At the time appointed I will return unto thee, according to the time of life, and Sarah shall have a son.
15 Then Sarah denied, saying, I laughed not; for she was afraid. And he said, Nay; but thou didst laugh.
==========
Later Sarah is described as a woman of faith ...
Heb. 11 ... 11
Through faith also Sara herself received strength to conceive seed, and
was delivered of a child when she was past age, because she judged him
faithful who had promised. 12 Therefore sprang there even of one, and
him as good as dead, so many as the stars of the sky in multitude, and
as the sand which is by the sea shore innumerable.