Truth is a very big deal in the Gospel of John. Jesus, in a good number of verses, begins his teachings with phrases like, “I tell you the truth.” In John 14:6, Jesus claims not only to speak the truth, but to actually be truth itself. In our text above Jesus says he came into the world to testify to the truth. Furthermore, he says, if you are on the side of truth you will listen to him.
It’s an incredibly bold move to say you are truth itself and your purpose for coming into the world is to testify to the truth. In fact, it’s downright arrogant, unless your claim is true. And that’s where the rub is. If it is true that Jesus is the truth, (and that he came to testify to the truth), then it would be prudent to listen to what he has to say. In fact, it would be an imperative.