'Forewarn' in the Bible

But I will forewarn you whom ye shall fear: Fear him, which after he hath killed hath power to cast into hell; yea, I say unto you, Fear him.

Those who cling to their old sins, and indeed all of you, I have forewarned and still forewarn (as I did on my second visit when present, so I do now, though absent)

envying, drunkenness, carousing, and things like these, of which I forewarn you, just as I have forewarned you, that those who practice such things will not inherit the kingdom of God.