1 John 2:19
They went away from us, but they were not of us. For, if they had been of us, they would have abode with us; but they went away, that they might be made manifest that they were not of us.
Treasury of Scripture Knowledge
Summary
While I was with them in the world, I kept them in thy name: those that thou gavest me I have kept, and none of them is lost, but the son of perdition; that the scripture might be fulfilled.
And
Bible References
And
1 John 2:19
They went away from us, but they were not of us. For, if they had been of us, they would have abode with us; but they went away, that they might be made manifest that they were not of us.