I also oppose using secular songs for worship. I think it is bordering on blasphemy when "worship" leaders sing songs like "J-E-S-U-S and Jesus was His name-o" or "ding dong the witch is dead, the wicked witch is dead (religion witch)". Those are two actual examples and I could list the artists that I heard sing those songs during worship.
What in the world is a 'religious witch'?
A spirit of religion or a religious spirit.
A cursory Google search leads me to believe that this is otherwise known as 'Phariseeism'. I have never heard this phrase before, in the Bible, or in Christianese.
I guess that growing up I heard people teach so much on the 'religious spirit' that I never thought about it being "Christianese". I think you see that kind of language used in some Reformed circles though when they talk for instance about religion saying something that contradicts unconditional election for instance. Some Reformed people would say that someone who teaches conditional election is peddling "religion". Mark Driscoll has used the word "religion" in this way. But then, he is a "Charismatic with a seatbelt".
I heard John Piper talking one time about how the adjective "religious" used to have a positive meaning as in the title of Jonathan Edwards's book "The Religious Affections" but now it has a negative meaning implying that someone is legalistic and pharasaical. In this case, the word "religious" is being used in opposite ways.
The Christian rapper Tedashii is featured in the Trip Lee song "Bear With You" speaks of true salvation and says "that's when it goes past religion".
Whereas Reformed people use the term "religious" to refer to doctrine that is counterintuitive to the Gospel, Pentecostals use the term to refer to worship that they feel is stodgy and restricting. It's just that the application in each case is different.
If 'religious' means 'pharasiacal' then what does 'pharasaical' mean? From your description it sounds like some Pentecostals have a 'spirit of a witch' in their view of us who are 'stodgy'.