Do some research (and by research I don't mean watch the DaVinci Code) and you'll find that the gospels and epistles (letters written by apostles) that are included in the bible were written within the lifetime of those who were eyewitnesses or directly knew the eyewitnesses within the first century of the church (except for Hebrews...that author is not identified...I can't explain that one). The gospel of Thomas is some gnostic gnonsense that was written in the century after the events.

You can start your research here if you want:
[link to y-jesus.com]

Or...just keep on believing whatever it is you want to believe and let God sort that out with you.