The Loftiest Level
Adam and Noach were not given more than seven commandments by God. If these were sufficient for them to achieve spiritual perfection, why was it necessary for the Jewish nation to be commanded so many hundreds more, and for Jews living in Eretz Yisrael to be required to observe all of the 613 mitzvos?
The answer is supplied by the Torah in these words:
Every mitzvah which I command you today you shall observe and fulfill in order to live and prosper, and to inherit the Land which God has vowed to give to your forefathers.
(Devarim 8:1)
Spiritual perfection has different levels. The level achieved through the seven Noachide commandments is a successful, disciplined life in both the relationship to God and to man. But in order to prosper spiritually and achieve a level which transcends time and place, it was necessary for Jews to be given the 613 mitzvot of the Torah. To achieve eternity and intimacy with God, they must also fulfill those special mitzvot connected with Eretz Yisrael so that they will inherit the Land whose spiritual power makes possible prophecy, the constant presence of the Shechinah (Divine Presence), and a miraculous existence. This is what God promised the first of the patriarchs when He vowed “I will give you the Land...and I shall be your God” (Bereishit 17:8).
(Rabbi Leibish Meir Malbim, Parashat Eikev)