Matthew 13:29

But he said, Nay; lest while ye gather up the tares, ye root up also the wheat with them.

But he said, Nay - `It will be done in due time, but not now, nor is it your business.'

Lest, while ye gather up the tares, ye root up also the wheat with them. Nothing could more clearly or forcibly teach the difficulty of distinguishing the two classes, and the high probability that in the attempt to do so these will be confounded.