How did god form his own people​

One day in the Middle East about four thousand years ago, an elderly but still rather astonishingly spry gentleman took his son for a walk up a hill. The young man carried on his back some wood that his father had told him they would use at the top to make an altar, upon which they would then perform the ritual sacrifice of a burnt offering. Unbeknownst to the son, however, the father had another sort of sacrifice in mind altogether. Abraham, the father, had been commanded, by the God he worshipped as supreme above all others, to sacrifice the young man himself, his beloved and only legitimate son, Isaac.