"The brain rules over the heart," which at first referred to impulse control and reigning in the impulses of the heart, now is explained to also mean changing the heart by slowly creating new feelings through meditation.
"It is very close to you--in your mouth, in your heart, to do it." Even the regular person can change his or her emotions enough to muster sufficient motivation to produce behavioral results. This is done through meditation.
Another way of finding motivation to do mitzvos is by activating the soul's latent love for G-d. All Jews possess the capacity to make the ultimate sacrifice in order not to be separated from G-d. If one understands how all sin separates one from G-d, and every mitzvah connects one to G-d, he or she will find sufficient motivation to adhere to all of the mitzvos.
What is the importance of joy? And how does one rid oneself of worries over material problems. (First half of Chapter 26.)
How do we overcome worry over spiritual problems, namely the guilt over past sins? (Second half of Chapter 26.)
Not only should one who has sinful impulses not be ashamed, he should rejoice in the opportunity to curb these impulses and thereby do a mitzvah.
Negating the popular misconception that if you experience distracting thoughts during prayer it means your prayers are worthless. The opposite may even be true.
We Addressing the problem of "timtum halev" (blockage of the heart) which causes a person not to feel. In this chapter, apathy is identified as an even more dangerous emotional state than sadness. Solutions are given for combatting the problem, primarily the use of personal inventory as a method of breaking down the complacency of the animal soul.
Continuing the theme begun in the previous chapter, namely leveling the false pride of the animal soul, we now discuss the importance of feeling humble before those who may be on a lower rung of religious observance (Ch. 30) and clarify that bitterness, as opposed to depression and apathy, can be a productive emotion (Ch. 31.)
The advice in the previous chapter, that of redefining our self image as soul-centered rather than body centered, is also the way to fulfill the commandment "Love your fellow as yourself." Only our bodies divide us; our souls are one.
(Significantly, the number 32 in Hebrew is ל"ב which also spells the word "lev" meaning "heart." This reminds us that ahavas Yisrael is the "heart of Tanya.")
One method for attaining joy is by contemplating G-d's absolute Oneness, meaning that even in this world, He is present. By doing so, we actually fulfill the very purpose of our existence which is to provide G-d a "dwelling place" in this lowest world. Thus, our joy is double and redoubled--we are happy that He is close to us; He is happy that He has a dwelling place in this world; He is happy for our happiness; we are happy for His happiness.
Another method for attaining joy is by considering the fact that since the destruction of the Temple, "The Holy One has no other sanctuary in this world than the four cubits of halachah. Thus, by engaging in the study of Torah at appointed times, one will be gladdened upon the realization that he merits to act as G-d's "host" in this world.
This joy, and other joys described in these chapters, in no way precludes a person from also feeling frustration over the limitations of his body and animal soul. As stated in the Zohar, "Weeping is lodged in one side of my heart and joy is lodged in the other."