Is the Bible the supreme authority?

No. This is a Protestant idea. Orthodox Christianity understands that both the Bible and the church fathers and mothers (the saints) work hand in hand to reveal everything we need to know. The Holy Spirit illumines the  saints and the church, and they guide us through the scriptures. The Bible is not the verbatim word of God. It is not a q'aran. The Orthodox do not believe this. We believe it is not just a single book, it is a collection of writings, authored by fallible but inspired man, containing many different genres, some literal, some not - all revealing the truth and reality of things. It contains history, allegory, prophetic writings, genealogies, apocalyptic literature, poetry and more. The Bible is the written source of truth, which goes hand in hand with, not above or beyond, the living Church.