This is the Speech of the All­Wise, the All­Knowing, which cannot be denied or opposed. and whose words can be truer than those of Allâh? (Of course, none). Allah explains in His Saying: And We have sent down to you the Book (the Qur'an) as an exposition of everything, a guidance, a mercy, and glad tidings for those who have submitted themselves (to Allâh as Muslims). that it also contains guidance, mercy and glad tidings besides being an explanation to everything. It is an explanation of the truth, its ways, methodologies and calling to it in the clearest statement and the most illustrative indication. It is guidance for the world regarding all they need from their Lord and what leads them to what pleases Him and makes them escape anything that brings about His Wrath. It shows them the way of success and happiness, in addition of being a mercy in explanation and instruction. It is guidance, benevolence, glad tidings and comfort for the hearts due to the explained truths and the guidance it gives to the insights that affect the hearts, relieve the souls, and open the hearts for them because of their simplicity and clarity. Allah (Glorified be He) says: O mankind! There has come to you a good advice from your Lord (i.e. the Qur'ân, enjoining all that is good and forbidding all that is evil), and a healing for that (disease of ignorance, doubt, hypocrisy and differences) which is in your breasts, ­ a guidance and a mercy (explaining lawful and unlawful things) for the believers. He (Glorified be He) also says: O you who believe! Obey Allâh and obey the Messenger (Muhammad ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭﺳﻠﻢ), and those of you (Muslims) who are in authority. (And) if you differ in anything amongst yourselves, refer it to Allâh and His Messenger (ﺻـﻠﻰ ﺍﷲ ﻋﻠﻴـﻪ ﻭﺳـﻠﻢ), if you believe in Allâh and in the Last Day. That is better and more suitable for final determination. He (Glorified be He) also says: And in whatsoever you differ, the decision thereof is with Allâh (He is the ruling Judge). (And say O Muhammad ﺻﻠﻰ ﺍﷲ ﻋﻠﻴﻪ ﻭ ﺳﻠﻢ to these polytheists:) Such is Allâh, my Lord in Whom I put my trust, and to Him I turn (in all of my affairs and) in repentance.

Had it not been that the Book of Allah (Glorified and Exalted be He) and the Sunnah of His Prophet (peace be upon him) contained guidance and enough knowledge, He would not have directed people to them. If resorting to them was not useful, He would not direct people to them in settling disputes and disagreement because of their power of guidance, clear explanation and solving problems and eliminating falsehood. Then Allah states that doing so is a condition of Iman (faith), saying: