To laugh — Abraham's face-down laugh at 17:17 mints the name Isaac (Yitschaq, 'he laughs'); Sarah's laugh (18:12) and her 'God has made laughter for me' (21:6) keep the pun running — until its sting: at 21:9 Sarah sees Ishmael metsacheq, 'laughing,' the participle of Isaac's own name-verb. Whatever he was doing, in Hebrew he was doing ISAAC — and it costs him his home (KJV 'mocking'; Douay 'playing'; Paul, 'persecuted,' Galatians 4:29). → first discussed at Gen 17:17