Sha’ar HaYihud VeHa’emuna (The Gate of Unity and Faith) is the second section of the Tanya, and it addresses the all-encompassing way in which God interacts with the world. The Divine is not only the source of the reality that He created – God enlivens and sustains it every moment from absolute nothingness. Yet this section does not just offer a theoretical analysis of the act of Creation. Its main thrust is the wondrous connection between created man and the Creator – man’s faith in absolute divine unity on the one hand and the presence of the Divine in every detail of creation on the other, which are nothing but two facets of the same reality.
Iggeret HaTeshuva (Letter on Repentance), the third section of the Tanya, constitutes a book in itself on the topic of repentance. It offers a deep exploration of the nature of sin and penitence, from which emerges a paradigm of the path to repentance. One learns that repentance is a process, beginning with the initial disconnection from sin and reparation of the blemish, followed by a higher level of repentance, where the present effectively erases the past, not only of the penitent, but of the entire creation.