Hi, jwanders!
We haven't met before I guess, though you've been here 4 months or so, so I want to welcome you to Bibleforums! 
It's great to have you here!!

Why do I believe in the Bible?
The main reason that I believe in the Bible is that I believe in Jesus Christ.
That is, I believe God exists, and I encounter the figure of Jesus in the Scriptures. His person, and his teaching, is unlike anything else I know: I am utterly convinced by this person: I believe what he says. He says, among other things, that He is the one sent by God to bring the truth. He, and those He taught testify that Jesus is the eternal Word, the Son of God. I believe Him. Thus, I believe the testimony that he chose to leave, which is found in the Bible.
Here's an objection -- and please feel free to voice any objections or questions you may have! -- which someone might raise to my thinking: "You are reasoning in a circle -- maybe Jesus wasn't like that at all. That is just how the New Testament documents depict him!" My reply would be that the figure of Jesus as depicted by the writers of the New Testament is a figure and a teaching so stunning that this Jesus, as pictured, is unlike anything else in the world -- and it must have come from someone. Jesus clearly is the one it came from In fact, this Gallilean peasant made such an impact upon his followers that they were prepared to die for him, gladly and in hope. Their descriptions of him presented a person so compelling that many many millions of people worldwide have come to put their trust in him. Where did this this arresting and powerful teaching come from. Obviously from some incredible figure. It's silly to suppose that it came from someone other than Jesus, for why would such a genius not have put forth that teaching in his or her own name; and why would those who followed it to death have died for a lie?
Some Additional Reasons
Of course, there are many other reasons I believe the Bible, and believe in Jesus. I don't want to make the post too long by giving details, but here are some.
1) I think that Christian doctrine -- especially the doctrine of the trinity -- i s the most compelling and sensible philosophical account of the universe
2) I think the moral psychology of the Bible gives a more insightful account of human nature, by far, than any other source
3) The more I read and study the Bible the more I am impressed by the profound coherence and wisdom of this book penned by many authors over many centuries and this I think is only accounted for by God's superintending and inspiring the whole Just for instance, I think that the philosophical, poetic depth of the Genesis account, and especially its opening chapters is a work so thoughtful and cogent that its fundamental truth is clear. This is true of parts of the Exodus narrative as well.
4) The coherence between the theological teaching of the Bible and the moral teaching of the Bible, and the narrative of Christ's life (and other events) which it gives profoundly confirms the depth, insight, and truth of the biblical witness.
There are other reasons which are, IMO, cogent, and which add to my conviction, but which I would not necessarily expect to convince those who have not come to know Christ.
4) I have seen how God works in the lives of believers, and especially in my own life.
5) I encounter God in prayer
6) The presentation of the basic worship of the church -- the eucharistic worship -- again presents Christ, and the truths of the Bible, with such power that I find it an important testimony in itself.
7) The same is true of the theology of the Fathers, and the creeds of the church, and in general the Christian witness through the ages -- the mere Christianity of which Lewis writes.
There are other reasons too, but these are some of the main ones.
Thanks for asking!
Feel free to say whatever you think or feel in response! I won't be offended!
In friendship,
Scruffy Kid
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