The legalism of Old Testament, concerning tithing, which they employ, does not hold any argumentative water at all. Abraham, who first offered his tithe did not have to comply out of any religious and coercive straitjacket terms. Father Abraham gave it out of sheer faith. Now we can comfortably say that God had no choice but to give an imprimatur to an idea solely envisioned by faithful Abraham, to bless HIS Israelites.

                It was not only a case of God knowing this in eternity of the past, HE was the One who deposited the thought into Abraham's heart. Amen.