'Wolves' in the Bible

Be on the watch for false prophets, who come to you in sheep's clothing, but inside they are cruel wolves.

See, I send you out as sheep among wolves. Be then as wise as snakes, and as gentle as doves.

Go on your way: see, I send you out like lambs among wolves.

I am conscious that after I am gone, evil wolves will come in among you, doing damage to the flock;