Revelation and reason or reason and revelation?

In our nowadays secularized community, religion is seen as sort of a hobby you do next to your necessary activities. The beliefs that are most important to our society are those of science, ethics, politics etc. Whether you believe in religion can have a place next to that and is completely and subjectively up to you. However, this hasn’t always be the case. Hundreds of years ago, religion played a much bigger part in the majority of people’s lives. If you did not conform to the religion prescribed by Latin emperors, you could be beheaded. Having polytheistic beliefs instead of monotheistic ones, could cause you to get into big trouble and so on. In medieval times religion was very important as well. They saw philosophy as a tool to understand their religion, whichever that was. Arabic thinkers had brought the tradition to the Jewish community of writing commentaries. When this habit continues for years and years you end up with loads of reports. These reports might have different opinions when considering the same subjects of the Jewish religion. Saadia Gaon al-Fayyumi was very concerned with this relation between reason and revelation. According to him, we needed to use our reason, because it’s the only tool that can protect us from making errors. With it, we can demonstrate and test these commentaries. Revelation then decides which interpretation is the best and consents with our idea of Jewish religion at that particular time. Revelation here is the jury to our rational judgement; the independent party to make the conclusion out of the information reason has provided us. 

We can see here that he creates a hierarchical structure where he places revelation above reason. He however doesn’t point out very clearly how he came to this distribution. He claims our reason should be considered more vague than scriptures and revelation. But aren’t these scriptures in the end a mixture of our reason and our own rational ideas of the right type of religion? Then why would revelation be of higher hierarchical status than reason, when it’s that much significantly intertwined? A obviously can’t test B, when there’s already a certain aspect of B in A. It’s then no longer an independent organ forming the conclusion. The conclusion of revelation is already formed by the reason that affected it in the first place.