Let no one deceive you in any way, for it will not come until the rebellion occurs and the man of lawlessness—the son of destruction—is revealed.
KJV
Let no man deceive you by any means: for [that day shall not come], except there come a falling away first, and that man of sin be revealed, the son of perdition;
ASV
let no man beguile you in any wise: for it will not be, except the falling away come first, and the man of sin be revealed, the son of perdition,