You also need to look at the Bible as a whole
That is a mistake that JWs and other bible-believing christians make. There is no such thing as 'the bible as a whole'. It is a collection of books which each reveal the different beliefs, biases and purposes of their authors.
The 'bible' has no coherent Christology.
How the author of Mark (whoever he was he wasn't Mark) understood Jesus in a very different way from the anonymous author of John, which again was different again from the OT prophets.