“By covetousness they will exploit you with deceptive words; for a long time their judgment has not been idle, and their destruction does not slumber.”
“Covetousness” literally means a desire to have more. “Covetousness” is a desire to have more in a bad sense (Ro 1:29; Ep 5:3; 1 Th 2:5). It is a strong desire to acquire more and more material possessions or possess more things that other people possess. This is irrespective of need.
Covetous false teachers want to possess financial gain for themselves. A covetous person always wants a larger portion of the pie. Religious con men grab the attention of religious people by offering them more than they now have. This is how false teachers extort others and satisfy their own greed.
False religionists make money out of their suckers.
We can tell a charlatan by whether they orient to greed. They exploit people for their own mercenary purposes. They turn their ministry into an exploitative marketplace.