Glow

A young woman has been exercising and eating well for months. One morning, she looks in the mirror and sees something different. Her skin looks soft and bright. Her eyes seem clearer. There is a warm, healthy light coming from her face that was not there before. She does not wear makeup or fancy clothes. The beauty comes from inside. What is her face doing? It is glowing (emitting a warm, soft light).

Glow means to emit a steady, soft, warm light, often from inside. Shine, by contrast, means to give out bright, often reflected light, like the sun or a polished surface. So, glow focuses on a gentle, healthy, inner radiance. Shine focuses on a stronger, often external brilliance that can be reflected or directed. In other words, a candle glows softly in the dark; a flashlight shines a beam across the room.