The Kestenbaum Edition Tikkun to receive updates of new ArtScroll releases and special offers. A young man complained to R' Mendel of Kotzk that he was unable to concentrate on prayer because he suffered from severe headaches. Prayer is with the heart, not with the head.
Emotions are a source of energy, and can be directed toward desirable or undesirable goals.
One can direct his anger toward other people, which is bad. Or one can direct his anger toward injustice, which is good. All emotions can be directed either positively or negatively. Many emotions are self-centered in a way that is detrimental to spirituality. The intellect must be put to work to turn the emotions away from physical desires toward spiritual concerns.