DEUT484 The main purpose of the precepts we perform with our bodies and limbs is to spur us to the precepts we fulfill in our hearts and inner lives; for they are the pillar of worship and the foundation of the Torah, as it is written: “Be in awe of Hashem your God; worship only Him” (Devarim 10:20); “It is a thing very close to you, in your mouth and in your heart, that you can do” (ibid. 30:14); “What does Hashem your God ask of you? Only that you fear Hashem your God” (ibid. 10:12). But since this [inner service] is beyond the [ordinary] power of a human being; [since] it is unattainable to him unless he detaches himself from his many animalistic desires, controls his instincts, and restrains his motions, the Creator, may He be exalted, has bound him to serve with his body and limbs, according to his ability, so that it becomes easier for him to fulfill them [i.e., the duties of the heart]. And when the believer works at them in his heart and inmost being and attains of them what he can, God opens for him the gate of spiritual virtues and he realizes of them what has been unattainable to him, and he serves the Creator, may He be exalted, with his body and soul, outwardly and inwardly, as David, peace be upon him, said: “My heart and flesh sing for joy to the living God” (Tehillim 84:3). This has been compared to a man who plants trees and then weeds around them, clears the soil of thorns and weeds, waters [the saplings] when this is needed and adds fertilizer. He then waits to receive the fruit from God, make He be exalted. But if he neglects to cultivate [the soil] and tend to [the saplings], he will not deserve to receive fruit from the Creator, may He be exalted. The same is true of one who undertakes God's service. If he exerts himself, hastens, and is diligent to do all that is in his power, God will help him achieve what is beyond his power, which is the noblest fruit and highest good bestowed by God in this world on His treasured ones and the people He loves. As our Masters, of blessed memory, said: “Whoever fulfills the Torah in the midst of poverty will, in the end, fulfill it in the midst of riches” (Avos 4:9); [As] the Wise One said: “To a person who finds favor before Him He gives wisdom, knowledge, and joy.” (Koheles 2:26).