Mankind was in trouble and needed to be saved. God had a plan to save mankind and that was through his Son. Before man can be saved God had to prove to man, that he was in trouble and needed to be saved. Hence God gave man the laws through Moses, what the laws did was to reveal sin so God can be proven right that man needed saving and man on the other hand could not make any excuse for their sins. To save man from hell, the debt that was owed to God...