Isacc
Isaac - his son.
Abraham's son Isaac was around 37 years old when he was almost sacrificed by his father.
No Moses is not the son of Abraham, it was Isaac who was Abraham son.
Abraham was a very old man, almost 100 years old when he had Isaac by his wife Sarah.
Isaac (Genesis ch.22). God tested Abraham's obedience by seeming to request that he sacrifice Isaac. See also:More about Abraham and Isaac
The son of Abraham and Hagar was Ishmael.
It was Abraham who was called upon to sacrifice his son (Genesis ch.22). But Isaac's life was spared when, at the last moment, God told Abraham that he may desist. The ongoing significance has been the Jewish readiness for devotion and self-sacrifice. As for Isaac specifically, it designates his children as the ritual heirs of a continuing relationship with the Divine whereas Ishmael (while having numerous offspring) was not so entitled.
Saul was a descendant of Abraham. He lived some 900 years after Abraham.
God tested abraham, as he told him to sacrifice Issac on mount Moriah.
Abraham's son = ben Avraham (בן אברהם)
Abraham had several wives Sarah, Hager and his sons were Isaac and Ishmael.
ihmael is the son of the woman that abraham really loved