Sounds almost too good to be true, doesn't it? That's probably why most people don't believe it. Oh, they may say they do, but if you look at their lives, it doesn't line up with what they're saying.
I'm not faulting anybody here, just observing. We look at our experience; we look at the world around us; we look everywhere but into the face of Jesus. That's why we don't believe it's true.
But if we look at the face of Jesus and remember that "all the fulness of the Godhead" dwells there—that the Father is just like the Son—then, and only then, can it become believable.
And a funny thing happens. We become like what we are gazing at; we become more Christlike. We become saints—which is what the Bible always calls Christians, by the way. We become a light in a very dark place...