The verses of the Shema begin with a commandment to “Serve G-d with all your heart. (Deut. 6:5)” The word for heart in the Hebrew text is written in a double manner—ordinarily, “with your whole heart” would be written as “Bchol Libecha,” but instead the word is written “Livavecha.” The Sages (Brachos 54a) say that the doubling of the letter “beis” connotes two hearts, referring to opposing inclinations within us. These two opposing inclinations are known as the Yetzer Tov – the desire to do good, and the Yetzer Harah – the desire to do evil.
What does it mean to serve G-d with both hearts, our desire to do good and evil? How can you serve G-d with a desire to do evil? To understand this, consider the following somewhat surprising statement the Sages of the Talmud make regarding the Yetzer Harah: It is as if G-d says, “I created the desire to do evil, and I created the Torah as its spice (Kiddushin 30b).” If the desire to do evil is inherently, well… evil, then why should it be flavored with spice to make it even better? Also, how would Torah, of all things, be its spice? Isn’t the Torah filled with G-d’s instructions to avoid what’s wrong and evil?
To understand this, consider the purpose of spice. It changes the flavor of the food, or adds flavor to something which has no taste. Our base desires are drawn to things which are enticing, that we sense will give us pleasure. Often the pleasure is not as good as we imagined, and it almost always doesn’t last. Torah, however, teaches the proper way to have pleasure. It changes the flavor from something disappointing and short lived, to something meaningful and long lasting. This means there is nothing inherently wrong with the desire for pleasure. It just needs Torah to give it the winning flavor.
It is in this way that we serve G-d with both our inclination for good and for evil. When we follow the recipe of Torah and Mitzvos the desire for evil, the desire to seek pleasure, is given its proper flavor, and serves to express our love of G-d, and not an attempt to turn away.