There are people who claim they have faith in Islam and are fairly acquainted with the Qur’an yet who readily disregard some of its rulings. According to popular "religion," those violating the fundamental commandments may be plagued by pangs of conscience, but neglect of those to which people attach little importance will not cause such discomfort, although they are also part of the Qur’an.
The purpose of this book is to serve as a reminder to people who have not realized their error or considered the penalty such an attitude will entail and summon them to live by the true principles of Islam, for Allah declares that man is responsible for all the commandments in the Qur’an, and warns that those who do not pay heed to His commandments will face torment in the Hereafter:
So do you believe in part of the Scripture and disbelieve in part? Then what is the recompense for those who do that among you except disgrace in worldly life; and on the Day of Resurrection they will be sent back to the severest of punishment. And Allah is not unaware of what you do. (Surat al-Baqara; 85)