Our beliefs are the convictions we have in our hearts. Thus, belief is from the actions of the heart and it is our hearts that Allah looks at and judges. This is because our hearts are the foundation from which speech and actions stem from.
This book is one of the books that introduce almost all aspects of Islam. It talks about Islam and its pillars. Moreover it talks about Eemaan and its pillars: believing in Allah, His Angels, His books and His messengers.
It is the time to believe in Islam, worship Allah the only true God, follow the Messenger of Mercy, the Prophet Muhammad peace be upon him, believe in the Quran the book of miracles.