phainō

In the active voice this word describes a light source doing what light does: casting its brightness out into the surrounding dark. It is what a lamp, a star, the sun, or the moon does simply by being lit.

The New Testament writers reach for it most often when light and darkness are set against each other. A lamp burns and shines, the true light already shines while the darkness is passing away, and the risen Christ's face shines like the sun. In the new creation the sun and moon are no longer needed to shine, because God's own glory lights the city.

This is a plain, physical picture, and it keeps its force even when the writers use it for spiritual truth: light that shines is light that others can see by.

When the same word turns to the receiving end (the middle and passive forms), it no longer means to give off light but to be seen. Something that was hidden or absent comes into view: an angel appears to Joseph, a star appears to the wise men, Elijah is said to have appeared, weeds show up among the wheat, lightning is seen across the sky.

From there it slides naturally into a second shade: not just to become visible, but to look like something to the people watching. This is the language of outward show. Whitewashed tombs look beautiful on the outside while hiding decay inside, and hypocrites take care to look righteous or to be seen fasting. The word can carry a neutral How does it seem to you? as easily as a pointed contrast between how a thing looks and what it really is.

The thread tying the two shades together is the viewer: in both, the word is about what registers on the eyes and judgment of an observer, whether a genuine appearance or a mere surface impression.