I once found this cartoon in my news feed depicting a man and a woman talking about Christian rock music. The woman asks his opinion about the music, and the man says "the words may appear to be God's, but the beat belongs to Satan. You tell me how can they be equally yoked together?" (emphasis mine).
Now, this particular clip seems to have come from a larger comic (my friend suspects it may have been drawn by Bob Larson, though I have been unable to confirm at this time). So, maybe the full strip depicts a greater dialogue I just haven't seen. Or, maybe that star in the speech bubble directs us to a Bible verse (though based on the wording, it probably just sends us to 2 Corinthians 6:14, which talks about not being unequally yoked with unbelievers). Unfortunately, I can only work with what I have been given.
But in truth, so can our fictional man. See, while many people tend to equate their opinions with God's opinions, God's revelation to mankind can be found in Scripture. If you need a text to say that, go to 2 Timothy 3:16-17. Here, we read "All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be complete, thoroughly equipped for every good work."
So, what is the ultimate purpose of Scripture? "that the man of God may be complete, thoroughly equipped for every good work." This leaves no room for ambiguity. If God intended us to believe Christian rock was actually Satanism disguised as Christianity, He would have made it clear.
Think of it this way: Pick literally any sin you can imagine. Adultery, covetousness, deceit, gluttony, sloth, murder, any of these will do. Now, how clear is the Bible on those things? The truth is, the Bible is very explicit. Whether in the form of "thou shalt not", or "the Lord hates (X)", or some other way, there are no sins in the Bible that come just from the opinion of the reader. If I want to prove adultery is wrong, I can go straight to Exodus 20:14 or James 2:11, both of which explicitly say adultery is wrong. I can even go a step further and say that things like porn are wrong, because Jesus said that to even look at a woman with lust is adultery in the heart (Matthew 5:28). We could do this with all the sins listed, and any more actual sins that have not even received a passing glance in this article.
Compare this with verses cited to show that rock music is sin. Don't get me wrong, there is such a thing as sinful music. You can use Scripture to show that songs using cuss words are evil, because the Bible condemns cussing (James 3:9-12). You can use Scripture to show that songs that blaspheme the Lord, glorify violence, or contain sexually immoral lyrics, are sinful, because you can show that these acts are likewise sinful from Scripture. But the beat alone? This is when ambiguity creeps in. The example given in this particular comic is being equally yoked. To say we shouldn't listen to Christian rock music because we shouldn't yoke light and dark together assumes rock music is dark to begin with.
There are other verses people use. Two other examples I saw not too long ago were James 4:4 and Ephesians 5:11. Read them, and you will see the same principle. They do not even touch on rock music, unless you first assume that Christian rock music is worldly, or is an unfruitful work of darkness. If you don't have that assumption, the verses do nothing to show we shouldn't enjoy Christian rock.
What's especially interesting is how God responds to music in the Old Testament. Needless to say, the New Testament is significantly more libertarian than the Old. The law of Moses was very restrictive. There were a number of restrictions most of us could not bear to live under. Yet, in Galatians 3:24-25 (among many others), Paul tells us that the law was our guardian until Christ came, and that now He has come, we are no longer under that guardian. In other words, the resurrection generally removes restrictions, rather than add them. Now take a look at God's attitude to music in the Old Testament. Where are the restrictions? Believe me my brethren, those who oppose rock music will struggle as much to find condemnation of music in the Old Testament as much as in the New. It's just not there. But what is there is a lot of music.
Most interesting to me is an instrument called a sistrum. If the Bible should call any instrument Satanic, this would be it. Not only is the sistrum an Egyptian instrument, but it was very specifically used in the worship of Hathor, an Egyptian goddess, whose image was often depicted on the handle. Yet, rather than call the sistrum demonic, the Bible actually shows David and the Israelites worshiping God with them (2 Samuel 6:5). And the dreaded cymbals, too. So, clearly, God has no issue even with genuinely pagan instruments. There would be quite the problem with the image of Hathor, or with using the sistrum to worship her, but shave her image off the instrument, and worship God instead, and just like that, the instrument becomes pure.
Now, if the significantly more restrictive Old Testament all but explicitly allows believers to praise God with a notoriously pagan instrument, and the significantly more libertarian New Testament does not condemn any music what so ever, where is the logic in saying the beat in a Christian rock song belongs to Satan? In fact, can anything God created truly belong to Satan? Goats are often associated with Satan, yet God owns the goats. Satan becomes particularly popular on October 31st, yet God does not take that day off. The truth is, even the most evil things Satan does are really just misusing good things. Every sin, great or small, exists only because a good thing is being abused. As a hole cannot exist without a doughnut, so also can sin not exist without good. Therefore, Christian rock can exist in the absence of sin.
And indeed, why would it not? Tell me, why would the devil want us to sing "Jesus be glorified", like Skillet do in the song "Jesus be Glorified"? Satan wants that glory for himself. He's not going to inspire his followers to give it to Jesus. And I would not want to meet the demon who speaks to Satan the way Toby Mac does in "Hey Devil", because if it is so powerful that it dares rebuke the king of demons, it will probably require a lot of prayer and fasting to drive away. Listen to "Oh the Depths" by Wolves at the Gate, and tell me, is that a message Satan's forces would want to spread far and wide? "Stranger" by Holy Soldier likewise presents the Gospel in such a clear way, no one would object to it if the tune was different. I could go on. These songs bear all the marks of a genuine Christian song. They don't belong to Satan, they belong to God. They were written for Him by His Church, using the skills He gave them for that very purpose. Where is the logic in saying they belong to Satan?
Answer: Zero logic. Indeed, using this logic, Scripture itself could become sinful. All you would have to do is put a Psalm to a beat and boom, even taking the Lord's words in your mouth becomes problematic. But for a believer, this should never be the case.
What we can say, then, is that this comic, and anyone who thinks like the man it displays, is in serious error. In fact, it repeats the error of the Pharisees: Preaching as doctrine the traditions of men. Music choice should always be left to the individual. If you regard rock music is unclean, to you it is unclean. You shouldn't listen to it because you don't think you can, and thus for you it is a genuine sin (Romans 14:23). But to those who are fully convinced in their own mind that it is no sin to praise God with rock music, it is entirely clean. This is one of those "doubtful disputations" that should make us individual parts of one united body, rather than cause us to squabble. Instead of slanderously accusing each other of worshiping Satan, let us all turn to Christ in praise.