Much harm can come to us by deceivers who say they are Christians but have not the Spirit

Dr. Joan Boney, Jesus Ministries ...

They come in pretense, often feigning humility, while inwardly they will eat you alive (if you let them) to get what they want.  Usually they want money from us.  

Sometimes they want to speculate and make themselves seem wise to themselves and others. 

When you speak the good word of God, they strike at you like a serpent, as they reveal themselves, and they grieve both you and the Holy Spirit.

Paul warns:   Titus 1:10-11   There are many unruly and vain talkers and deceivers, specially they of the circumcision:  Whose mouths must be stopped, who subvert whole houses, teaching things which they ought not, for filthy lucre's sake.

Here are some other warnings in Bible about church people who are trying to gain entrance, but for evil motives.

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