What does 1 Corinthians 11:15 mean?

Paul is making one last argument in favor of women covering their heads when praying or prophesying in Corinthian worship services. He pointed out in the previous verse that nature demonstrates the male tendency to keep hair shorter. Relatively speaking, "shorter" hair is typically considered a male trait, and "longer" hair a female trait. Men are disgraced when they violate this standard, as most cultures see this as an expression of femininity.

Now he says that, even from the natural perspective, long hair is glory for a woman. In most cultures and times, women naturally wear their hair "longer," particularly in comparison to men. In this way, it serves as a natural covering. Paul does not seem to be saying that long hair is a substitute for an additional head covering when the Corinthian women are praying or prophesying in church services. Rather, his point is that the near-universal association of "longer" hair with femininity supports the idea that a covering is needed.

The general principle Paul has revealed in all of this is that of modesty with respect to culture. Christians ought not send "mixed signals" with their behavior, dress, or personal style. In the era when Paul wrote these words, a woman with an uncovered head in public was not unlike a modern-era woman wearing a revealing bathing suit to church. Obviously, specific cultural standards have changed; the principle remains the same. Believers—both male and female (1 Corinthians 11:4–5)—are obligated to consider the social implications of their appearance.