You will notice that the word "truth" was in quotes.
That was not accidental.
Jesus claimed He was God and thus, it is only Him, His teachings, that one looks at to scrutinize.Since He is God, it is also only Him that can tell anyone who the God of the Old Testament is.
... That leads me to believe He is who He said He is.
Do you have an example where He contradicts Himself, or displays He has some nature of a tyrant?