When one fulfills a mitzva, he acts as a sanctuary for God, despite there being evil aspects that still exist within him.
Only certain rare individuals succeed in transforming the nature of their souls and purifying them through and through.
Most people must content themselves with the knowledge that their darker aspects are buried under many layers, and at best they need to make certain that they are not brought to the fore, as alluded to in• the verse “A shameful matter shall not appear among you” (Deut. 23:15).
Rabbi Adin Steinsaltz