One of the biggest reasons you can trust the Bible is that Jesus did. He affirmed the writings of the OT (Matt 5:17-18; John 10:34-36; Luke 24:25-32) and promised what would become the NT (John 14:26; 16:12-14). And if Jesus is who he claimed to be and God did in fact raise him from the dead, then his testimony is powerful evidence that the Bible is truly God’s word to us (2 Tim 3:16-17 cf. 2 Pet 1:20-21). Trusting the Bible is not a blind leap of faith, it is an entirely reasonable thing to do.