An impartial eyewitness would expect people to follow what brought them from adversity to prosperity. But in Islam, it appears that the believers ended up following tradition rather than revelation. How did this happen? Why did the believers begin to follow their predecessors rather than revelation? How did their predecessors become mediators in their universe? This was a faux pas that would affect the ummah in adverse ways. Revelation was replaced by temporal guidance. The believers began to follow traditional rather than revealed Islam. As a result, Muslims find themselves in the straitjacket of tradition, which transmuted into a fetish. Tradition is treated as an "equal," a "judge" and even "abrogator" of revelation. The elevation of tradition to revelation and even above revelation was an expression of paganism, as it entailed associating a partner with, and even postulating the existence of a being "greater" than God. But no one is "greater" than Allah. The word of man differs from the word of God. Tradition is different from revelation. Tradition is man-made. Revelation is divine. Tradition emerges from revelation and is neither "equal" nor "similar" to revelation. To be relevant and authentic, tradition is required to follow revelation. But it appears that revelation was expected to follow tradition. Tradition affected the knowledge of revelation through unwarranted practices, for example the teaching of abrogation. As a result, the substantive teaching of revelation differs from that of tradition. Tradition drifted from revelation in key aspects, even becoming "independent" of the law. How could this be when it was revelation that spawned tradition in the first place? It appears that the deterioration was triggered by a breakdown of reason. Reason was shunned aside, as unfit to appreciate revelation. But this was a fateful step. For reason is required not just to understand but also to apply revelation. The following error was the designation of tradition as revelation. The latter is rich, addressing all aspects of life. By contrast, tradition is truncated; essential parts of the teaching of revelation are absent. Revelation emphasises justice, ethics, and reason; but we find few books addressing justice, reason or ethics in the traditions. But there is a plethora of traditions explaining the way to pray. What explains this aberration? The elevation of tradition to revelation facilitated the fusion of tradition and revelation. The fusion brought confusion. Blurring the difference between tradition and revelation enabled traditions to "judge" and even "abrogate" revelation. However, abrogation did not take place without a corruption of the knowledge of revelation. Rational analysis requires recognising and being alert to differences. When reasoning atrophies, knowledge deteriorates. In Islam, using reason to understand revelation was associated with kufr or non-belief, based on a fabricated tradition. As a result, reasoning deteriorated to the point of producing a "crisis in the Muslim mind." The denigration of reasoning made it harder to understand and therefore to follow revelation. It tainted the knowledge of revelation and triggered the disintegration of an empire. Will any nation flourish without the use of reason? Reason is the key to knowledge. The attainment of knowledge requires the use of reason. To reject reason is to dispense with the key to knowledge, to fall back into darkness. The renewal of the Muslim civilization thus requires recovering the knowledge of revelation, which presupposes the rehabilitation and re-engagement of reason for the purpose of understanding and following revelation.