"Allah has created you and what you do" (Qur'an 37:96);
This knowledge is a branch of the sciences of Sacred Law that originated within the Umma. From the first, the way of such people had also been considered the path of truth and guidance by the early Muslim community and its notables, of the Companions of the Prophet (Allah bless him and give him peace), those who were taught by them, and those who came after them.
"It is He who created you and what you do" (Qur'an 37:96).
As we sat one day with the Messenger of Allah (Allah bless him and give him peace), a man in pure white clothing and jet black hair came to us, without a trace of travelling upon him, though none of us knew him.He sat down before the Prophet (Allah bless him and give him peace) bracing his knees against his, resting his hands on his legs, and said: "Muhammad, tell me about Islam." The Messenger of Allah (Allah bless him and give him peace) said: "Islam is to testify that there is no god but Allah and that Muhammad is the Messenger of Allah, and to perform the prayer, give zakat, fast in Ramadan, and perform the pilgrimage to the House if you can find a way."He said: "You have spoken the truth," and we were surprised that he should ask and then confirm the answer. Then he said:"Tell me about true faith (iman)," and the Prophet (Allah bless him and give him peace) answered: "It is to believe in Allah, His angels, His inspired Books, His messengers, the Last Day, and in destiny, its good and evil.""You have spoken the truth," he said, "Now tell me about the perfection of faith (ihsan)," and the Prophet (Allah bless him and give him peace) answered: "It is to worship Allah as if you see Him, and if you see Him not, He nevertheless sees you."
Then the visitor left. I waited a long while, and the Prophet (Allah bless him and give him peace) said to me, "Do you know, ‘Umar, who was the questioner?" and I replied, "Allah and His messenger know best." He said,"It was Gabriel, who came to you to teach you your religion" (Sahih Muslim, 1.37: hadith 8).
"Ask those who know if you know not" (Qur'an 16:43),
"Allah has truly blessed the believers, for He has sent them a messenger of themselves, who recites His signs to them and purifies them, and teaches them the Book and the Wisdom" (Qur'an 3:164),
"And follow the path of him who turns unto Me" (Qur'an 31:15).
"There is nothing whatesover like unto Him" (Qur'an 42:11)
"Say: ‘The soul is of the affair of my Lord’" (Qur'an 17:85).
"Shall I not tell you of the best of your works, the purest of them in the eyes of your Master, the highest in raising your rank, better than giving gold and silver, and better for you than to meet your enemy and smite their necks, and they smite yours?" They said, "This—what is it, O Messenger of Allah?" and he said:Dhikru Llahi ‘azza wa jall, "The remembrance of Allah Mighty and Majestic." (al-Mustadrak ‘ala al-Sahihayn, 1.496).