"For I know this, that after my departure savage wolves will come in among you, not sparing the flock. Also from among yourselves men will rise up, speaking perverse things, to draw away the disciples after themselves." (Acts 20:29-30)

Damage to the body of Christ usually comes from within rather than from without. When one cuts into an apple or, worse, bites into it, and finds a worm, the worm did not come from outside the apple but from the inside. An adult moth laid an egg in the heart of the flower. The egg was then incorporated into the ovary, and finally into the mature flower's fruit, the apple. Thus, when you find a worm's hole in the rind of the apple, the worm has already done its damage, and is off to pupate into an adult moth which lays more eggs in future flowers the same way. And, until the cycle can be broken by the farmer, much fruit will continue to be damaged.

Paul continue, "Therefore watch, and remember that for three years I did not cease to warn everyone night and day with tears. So now, brethren, I commend you to God and to the word of His grace, which is able to build you up and give you an inheritance among all those who are sanctified." (Acts 20:31-32)