Midrash Rabbah Beresheet on Using Body Parts to Do Good Works

"Rabbi Levi said: There are six things that serve a person, three of them are under the person's control and three are not under his control. The eye and the ear and the nose are not under his control, for he sees what he does not wish to see, hears what he does not wish to hear, and smells what he does not wish to smell.

"The mouth and the hand and the foot are under a person's control. If the person wishes, his mouth can engage words of Torah, but if he wishes it can engage in malicious speech; if he wishes, his mouth can even disgrace and blaspheme God. Similarly, the hand can perform commandments, but if the person wishes, his hand can steal; or if he wishes, his hand can even commit murder. Likewise, the foot is under his control, for if he so wishes, his foot can go to the theaters and circuses, or if he wishes his foot can go to to temples and study halls."

-- Midrash Rabbah, Beresheet 67.3