Bible Verses About Union With Christ: Our being in Christ

I know a man in Christ, fourteen years ago (whether in the body, I know not; or whether out of the body, I know not; God knoweth), such a one caught up even to the third heaven.

And we know that the Son of God is come, and hath given us an understanding, that we know him that is true, and we are in him that is true, even in his Son Jesus Christ. This is the true God, and eternal life.