None. because ...
Definitely not in circles for me. What made me believe the bible is the Word of God is not because the bible claims it is but by my own common sense.
It is the only book I know who has a better explanation for the beginning and the end of all things.
The bible means "collection of books" which was written from different generations by different writers with different professions. And yet with continuity and harmony as if there is only one author. 2000 years difference when the 1st and the last book was written so it is impossible it is just man-made but coming from an eternal and very intellectual being(even just for this reason deserve to be called God). Can you tell me the difference between movies authored, written and directed by different people(like the spiderman,superman,batman series) and those from one author like Hobbits+Lord Of The Rings and Harry Potter series? The bible was written by different men but same author from the very beginning.
The prophetic words in it is with 100% accuracy. From the past, present and even future events. Any error invalidates its integrity and it is consistent as far as I know so I continue to believe.
There was indeed an historical record(not just biblical) of Jesus Christ, the central figure of the bible. The historical record also claims His teachings, miracles, death and resurrection which means Jesus is not a liar and not a lunatic but Jesus is Lord as what the bible says.
And most of all, it has help me transform my life, my character, and my future. There was a big difference with my old and with my new life in the Lord Jesus. Just like in +2 Cor 5:17 "Therefore, if anyone is in Christ, he is a new creation; old things have passed away; behold, all things have become new."
And this is the greatest miracle when you truly believe in the God of the bible.