Page 66 - BERESHIT

When Adam was expelled from Gan Eden, Hashem clothed him with a
garment of light. The Ben Ish Chai explains from the Arizal that this
garment was to aid him in his battle against the Yetzer Hara. He needed
this help only after he sinned, because until then, he did not have an evil
inclination to deal with.

Why did Adam not merit remaining in Gan Eden after he recognized his
sin? The explanation lies in the difference between the teshuvah of David
Hamelech and that of Shaul Hamelech. Shaul Hamelech did not admit his
guilt until after he was reproved by Shmuel. David Hamelech, on the other
hand, immediately accepted the reproof of Natan Hanavi and repented.

For this reason, Adam’s acknowledgment did not find favor in Hashem’s
eyes. It is not enough to refrain from further sin. One must also
immediately confess. Because he did not do so, Adam did not deserve to
remain in his exalted state and was expelled from Gan Eden.