Who decided which books make up the Bible? How do we know which books belong in the Bible and which books don’t?
The question is dealt with in the first 3 minutes of this video by Dr Michael Kruger (Reformed Theological Seminary, Charlotte):
It’s also answered in more detail below in a 13-minute video by Dr Robert Plummer (Southern Baptist Theological Seminary):
Update: For a short book on the subject, check out A Christian’s Pocket Guide to How we Got the Bible. Michael Kruger (above) comments: ‘Finally, we have an accessible book on the biblical canon that is answering the kind of questions ordinary Christians are asking. I highly recommend it.’