'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.

and if Christ has not been raised, your faith is worthless and powerless [mere delusion]; you are still in your sins [and under the control and penalty of sin].

that, regarding your previous way of life, you put off your old self [completely discard your former nature], which is being corrupted through deceitful desires,

For our appeal does not come from delusion or impure motives, nor [is it motivated] by deceit [our message is complete, accurate, and based on the truth—it does not change].

And for this cause God shall send them strong delusion, that they should believe a lie:

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