For he had confident hope in that which was past hope, that he should become a father of many nations, according to that which was spoken, "Thus shall thy offspring be;"

But what saith it? "The word is nigh thee, in thy mouth, and in thy heart;" that is, the word concerning faith, which we preach;

Through faith Sarah herself also received power to conceive, even when she was past age, because she accounted him faithful who had promised.

General references

But ye, brethren, as Isaac was, are children of a promise.