The religious sciences of Islam, in their diversity, respond to the needs of the community and of the believer. They originated in the Quran and the Sunnah. They evolved and were structured during the first centuries of the Hegira.

In this book it is a question of the purification of hearts and it is tassawuf (Sufism) the appropriate science, this discipline is an integral part of Islamic sciences. If fiqh teaches us to read the Koran correctly, grammar teaches us to educate our souls (nafs) and to purify the heart qalb, this heart about which God says "The day when neither goods nor descendants will be of less useful, except the one who will appear before God with a pure heart" (Koran, 26, 88-89), and on which the Prophet said: "God does not look at your forms but only looks at your hearts. "