'Delusion' in the Bible

Do you not know that unrighteous men will not inherit God's Kingdom? Cherish no delusion here. Neither fornicators, nor idolaters, nor adulterers, nor any who are guilty of unnatural crime,

And if Christ has not risen, it follows that what we preach is a delusion, and that your faith also is a delusion.

For our preaching was not grounded on a delusion, nor prompted by mingled motives, nor was there fraud in it.

But prove yourselves obedient to the Message, and do not be mere hearers of it, imposing a delusion upon yourselves.