““The Isaac stories open (cf. v.11) with a final statement regarding the line of Ishmael, consisting of a genealogy of the twelve leaders of Ishmael’s clan, a report of the length of his life, and a report of his death. The number twelve appears again to be a deliberate attempt to set these individuals off as founders of a new and separate people (see comment on 22:20 – 24). The descendants of Ishmael continue to play a part in Genesis (28:9; 36:3; 37:27 – 28; 39:1).””
