'Fall Away' in the Bible

Then Jesus said to them. "This very night even you will all stumble and fall away from me; for it is written, 'I will smite the shepherd, and the sheep of the flock will be scattered.'

"If they all stumble and fall away from you," answered Peter, "I will never do so!"

but because they have no root in themselves they last for a time; but when suffering or persecution ensues because of the Word, they at once fall away.

"Those on the rock are people who, upon hearing, receive the word with joy; but they have no root. For a time indeed they all believe, but in time of temptation they fall away.

Now the Spirit distinctly declares that in latter days there will be some who will fall away from the faith, by listening to spirits of error, and to teachings of demons