John

Then said Jesus to those Jews which believed on him, If ye continue in my word, then are ye my disciples indeed;

And Jesus said unto him, No man, having put his hand to the plough, and looking back, is fit for the kingdom of God.

They went out from us, but they were not of us; for if they had been of us, they would no doubt have continued with us: but they went out, that they might be made manifest that they were not all of us.

Many therefore of his disciples, when they had heard this, said, This is an hard saying; who can hear it?

Now the just shall live by faith: but if any man draw back, my soul shall have no pleasure in him.