Why Should I Believe the Christian Bible NOT Other Religions?

Look for fulfilled prophecy in other religions. You won't find it. In Western culture, we're used to the concept of prophecy because our culture was founded on Christian principles, so we tend to take it for granted - we assume that's just what religions have. But that assumption is wrong. Look at other religions and you won't find a body of fulfilled prophecy. That is why God points to His prophecy fulfillment as proof that He exists in Isaiah 46:10 - "I make known the end from the beginning, from ancient times, what is still to come. I say, ‘My purpose will stand, and I will do all that I please.’" If you doubt Christianity, the existence of God, and the veracity of the Bible, research fulfilled prophecy. God will meet you there.