1. Does a song need to mention God or Jesus, or imply that God exists in some way?
There are numerous Proverbs in the Bible that don’t mention God. There is even an entire book in the Bible that doesn’t mention God in any way: Esther. Based on the example of the Bible, the answer would be no.
2. Should we avoid music depicting sex and violence?
One of the big critiques of so-called secular music (and books, movies, art, etc) is how often they depict immorality, violence, and other un-Godly things. If you read the Bible cover-to-cover, there are some rather disturbing depictions of immorality and violence. Rape and incest (1 Sam 13), babies smashed against rocks (Psalms 1:9), and the rather horrible story in Judges 19-20 are among them. Then we have the rather sensual poem otherwise known as the Song of Solomon. Based on the Bible itself, it appears the mere presence of sex and violence isn’t enough to avoid it. Context is important, as is learning to discern truth.
3. Doesn’t the Bible tell us to think about things that noble, pure, and lovely?
“Finally, brothers, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable–if anything is excellent or praiseworthy–think about such things.” -Phillipians 4:8
Very true, but the Scripture doesn’t say we should only think about such things. I do believe that what we read, see, and think about affects us, but we can’t live in denial of what is going on in the world around us. There is pain, suffering, abuse, murder, and violence all around. Sometimes these things are even in our own hearts. Pretending that the world is all sunshine doesn’t make the darkness go away. Surrounding ourselves with only ideas that are comfortable doesn’t create a culture where we are free to enter other people’s pain or share with one another. We ‘should’ dwell on truth, and there are many voices competing with that truth. What we ‘should’ also be doing is spending time in prayer and resting from work so we can DISCERN truth when we hear it.