the child of Sara (child of the wife/one-flesh) sounds convincing but falls apart in the very next generation. comeback: Oh but Esau did bad things, he wrote himself off. so the line of Jesus has no bondwoman, harlots, broken people .... oh dear. 1 generation fail, 10 generations failed 4 times. instead of your long drawn out theory - that fails, read the Word ... hint: "child of promise" - and that is it in totality, God chose, God said (promise), God did. No need to for your own (contemporary) interpretation - please, just read the Word ... righteousness ... are you going to follow and believe the word of God or the idea's of man?
