Genesis 21:9-21- Ishmael
The Christian tradition has a mother and father who are almost perfect, certainly annoyingly good and bathed in an innocent and almost sugary light. The way we've come to imagine Mary and Joseph is almost insipid.
The mother and father of the Jews are not quite like that. Abraham and Sarah are a lot more three dimensional, far more human. The two of them scheme with Pharaoh as well as God.
Anyway, there are two sons in the family: one is the one born late in life - Isaac and the other, Ishmael, born earlier to Hagar, Sarah's Egyptian handmaid (it was Sarah's idea...) but one day Sarah finds Ismael laughing (The bible says 'playing' but the word is closer to the name of Isaac!). She wants Abraham to get rid of both him and his mother. How easily things turn when the shoe is now on the other foot.
And so they are thrown out into the desert with some bread and that's about it. they are left to die by the great Patriarch.
They don't but that's God's doing rather than anyone from Sarah and Abraham's family and tradition has it that from Ismael grows the Arab nations.
It is the root of prejudice, fear, bitterness: O why can we not learn that we ought to remember our origins. We come from the one stock, the one story, the one source. Somehow we forget the similarities and find prejudice and fear reshapes how we see those origins.
It is a significant story to hear on Remembrance Sunday.