“And she said, Who would have said unto Abraham, that Sarah should have given children suck? for I have born him a son in his old age.”
King James Version (KJV)
21:6 And Sarah said, God has made me to laugh - He hath given me both cause to rejoice, and a heart to rejoice. And it adds to the comfort of any mercy to have our friends rejoice with us in it, See #Luke 1:58|. They that hear will laugh with me - Others will rejoice in this instance of God's power and goodness, and be encouraged to trust in him.
21:9 Sarah saw the son of the Egyptian mocking - Mocking Isaac no doubt, for it is sad, with reference to this, #Gal 4:29|, that he that was born after the flesh, persecuted him that was born after the spirit. Ishmael is here called the son of the Egyptian, because (as some think) the four hundred years affliction of the seed of Abraham by the Egyptians began now, and was to be dated from hence.