I am teaching right now in my philosophy class on meaning in music. When beginning any discussion like this, I always find that it is important to address how the authority of Scripture factors in.
I begin with 1 Timothy 3:16-17:
All Scripture is breathed out by God and profitable for teaching, for reproof, for correction, and for training in righteousness, that the man of God may be complete, equipped for every good work.
Scripture governs absolutely every area of our lives; there is nothing the Bible does not address, either by precept, principle, or example, including our music.
The question then becomes, what in Scripture governs our music? To answer this question, we must understand the nature of music itself.
Music is not a thing; music is an action. Specifically, music is an action of moral human agents. While God created the “stuff” of music (sound, pitch, rhythm, timbre, etc.), moral human agents create songs.
Scripture is clear that the actions of moral agents are either good or evil. By the common grace of God, people can do good things (Luke 6:33; Rom 2:14-15). They can also do sinful things (1 John 1:8).
Specifically, music is communication. Although Scripture is not intended to be a music textbook and should not be viewed that way, Scripture at least implies that music communicates. Here are just a few examples:
Instrumental music can express victory or defeat (Exod 32:17-18), calm (1 Sam 16:1-23), mourning, weeping, and wailing (Job 30:31; Isa 16:11; Jer 48:36), joy (1 Chr 15:16), and pomp (Isa 14:11). This kind of communication may be common to all people or specific to a culture, or even specific to a certain person. Again, Scripture doesn’t teach that music communicates, but it implies what we know by experience.
Scripture says that human communication must be evaluated. Communication can express anger, wrath, malice, and obscenity (Col 3:8). Communication can be corrupt or edifying (Eph 4:29). Furthermore, Scripture’s principles concerning communication apply to all forms of communication like body language or facial expressions (even a “look” can express pride [Prov 6:17]), not just propositions.
Thus, what Scripture says about communication must be applied to music. In particular, music communicates similarly to tone of voice and body language. Assuming what we say is good, if our tone of voice expresses love, joy, peace, patience, kindness, goodness, faithfulness, gentleness, or self-control, it is good; and if our tone of voice expresses impurity, sensuality, enmity, strife, or fits of anger, it is sinful ( 5:19-20, 22). It can express these things even if we don’t intend them, such as when I speak harshly to my wife after a long day even though I do not intend to.
Making evaluations about what tones of voice express what emotion is not always easy; it requires wisdom and judgment. But if we long to be conformed to the image of Christ, we’ll make those judgments about all of our communications.