Gen 21:1-14. Interesting to see the frequency of laughter in the Isaac story.
--While laughter isn’t mentioned in 16:4-5, still one can imagine Hagar’s looking down with contempt on Sarah (for her inability to conceive) to be expressed in an evil laughter.
--Sarah’s laughter in 18:10-12 seems to be a laughter of unbelief that she would bear a son as the divine visitor suggested. Thus does Sarah seem to laugh at herself for the same reason Hagar laughed at her.
--When the Lord questions her laughter (18:13-15), Sarah denies it out of fear, but the Lord knows the truth.
--Even before Sarah conceives, the Lord instructs Abraham to name the boy Isaac, which means “he laughs” (17:19).
--At Isaac’s birth, Sarah acknowledges the laughter—a joyful laughter—God has given her in Isaac, and she claims that everyone will laugh (presumably in a good way) over her when they find out (21:6-7).
--But when she sees Ishmael laughing, she stops laughing. Perhaps seeing in Ishmael what she had seen in Ishmael’s mother some 14 years before resurrects old wounds, and she puts both laughers out (21:9-14).
--In sum, I guess laugher isn’t always a laughing matter.
Gen 21:15-21. Hagar was impressed with God as the God Who Sees when Sarah threw her out the first time when she was pregnant with Ishmael (16:13-14). He saw her in her misery and looked after her. The second time she and Ishmael are thrown out, God “hears” their cries (21:17) and then he opens “her eyes” to a well of water nearby, and he promises to make Ishmael into a great nation. And for the next several years “God was with the boy, and he grew up.”