Satan does not mind you being sincere (Rom. 10:1-2), he does not mind you being religious (Php. 3:5-6), he does not mind you preaching and performing miracles (Mat. 7:21-23), he does not mind you confessing your sins (Ex 10:16), he does not mind you listening to a sermon and enjoying it (MK 6:20)....
....so long as in all these things you don't truly repent and put your trust in Christ Jesus alone for salvation. That's just fine with him.
