God’s first commandment to man came directly from the Creator in Genesis 2, when God told Adam and Eve not to eat of the Tree of Knowledge of Good and Evil. Sin entered the world when Adam and Eve disobeyed God’s commandment. Death was the consequence of that original sin.
Moses brought a new set of direct commandments from God and situated man in the same position as Adam. We can disobey the direct commandments of our Creator. But, Jesus completed the cycle of sin and death by bringing redemption and life. Adam was the first man, and many call Jesus the second man and the second Adam. Romans 5 tells us sin and death came through one man — Adam — and the freedom from death came through one man — Jesus Christ.
ROMANS 5: 12-14
12 Wherefore, as by one man sin entered into the world, and death by sin; and so death passed upon all men, for that all have sinned: 13 (For until the law sin was in the world: but sin is not imputed when there is no law. 14 Nevertheless death reigned from Adam to Moses, even over them that had not sinned after the similitude of Adam’s transgression, who is the figure of him that was to come.