Fitrah is detector in our brain to detect existence of God and knowing what is right and knowing what is wrong Which Is The Best Religion Of Allah ? Quran 30:30 '' O (Muhammad), be devoted to the upright >>religion<< It is harmonious with the >nature< which God has >>designed for people<< The design of God cannot be altered. Thus is the >>upright religion<< but many people do not know. Quran 1:172 Sahih International : And [mention] when your Lord took from the children of Adam - from their loins - their descendants and made them testify of themselves, [saying to them], "Am I not your Lord?" They said, "Yes, we have testified." [This] - lest you should say on the day of Resurrection, "Indeed, we were of this unaware." Pickthall : And (remember) when thy Lord brought forth from the Children of Adam, from their reins, their seed, and made them testify of themselves, (saying): Am I not your L