Beauty has been classically defined as that which pleases when apprehended (Thomas Aquinas). Both terms in that definition are worth considering.
First, "apprehended." Beauty can describe things, persons, or ideas—anything that can be apprehended by the mind, and this apprehension may or may not involve the physical senses. Seeing, smelling, hearing, or tasting call all bring pleasure, but so can contemplating something purely abstract, such as a math theorem or a chess game.
Second, "pleases." Aesthetic pleasure is not just any pleasure. In other words, beauty isn't the only thing that produces pleasure. Some pleasures occur as a result of a need being met, such as the pleasure derived from drinking a cool class of water on a hot day.
Aesthetic pleasure is different because it is pleasure that comes regardless if a need is met. This kind of pleasure has traditionally been called "disinterested pleasure." It is pleasure taken in something simple for itself rather than because that thing has met a need.
The other important factor is the nature of the relationship between beauty and pleasure. Another way to put the issue is whether beauty is relative or absolute. In other words, is something beautiful because it brings pleasure, or do things bring pleasure because they are beautiful?
The biblical answer to this question is that absolute standards of beauty exist that produce pleasure for the following reasons:
First, the self-existence of God demands absolute beauty (John 17:5, 24; Rev 4:11). Just as truth and morality find their source in the nature and character of God, so objects may be rightly called beautiful, not if someone simply delights in them, but if they likewise reflect Supreme Beauty.
Second, Scripture calls God beautiful (2 Chron 20:21; Job 40:9-10; Ps 9:8, 27:4, 45:2-4, 104:1, 145:10-12, Isa 42:14, Zech 9:17), further confirming that God is the ultimate standard of beauty. God's glory is his beauty.
Third, in Scripture God declares particular things beautiful. He called his new creation beautiful (Genesis 1:4, 10, 12, 18, 21, and 25), and he prescribes specific artistic instructions for liturgical adornments so that they would manifest "glory and beauty" (Exodus 28:2).
Fourth, in Scripture God commands that Christians delight in what is truly beautiful. For example, Philippians 4:8 commands believers to "think on" things that are "lovely" (literally "towards affection"), "commendable" (admirable), and "worthy of praise." These are terms each closely connected to our conception of beauty, and they imply that there are things both worthy and unworthy of delight.
Thus beauty is absolute. Christians should take pleasure in only those things worthy of pleasure, and what determines that worthiness is conformity to the beauty of God himself.
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