The holy Quran is believed by all Muslims as the basis of thinking how they should govern their lives. The Quran says: Those who do not judge by the law which Allah has sent down, are indeed the disbelievers” (Al Maida 44).
When Quran declares something unlawful, no authority can challenge it, therefore no other source of law can go against Quran. For example since the Quran prohibits gambling, any form of gambling is unlawful. All other three sources will agree with this principle and there is no conflict between them.
The Sunnah is the second primary source of Islamic law. It is next to Quran in authority. It is important because Allah Himself gave authority to the Prophet Mohammad (saw) to make laws. The Quran says:“So take what the messenger gives you, and refrain from what he prohibits you.” (Al Hashr 59:7).
It is also important because without Sunnah we can never understand Quran. For example, the Quran does not tell us how to perform Salat. The method is given by the Prophet (saw). The Quran and the Sunnah never contradict each other. Sunnah is only an extension and explanation of the Quran. Sunnah is an authority where the Qran is silent. The Quran says: “—He makes pure things lawful for them and impure things unlawful” (Al Aaraaf 157)
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