Shakespeare’s speaker urges a young man to stop gazing at himself and have a child. The argument is blunt: we want the loveliest creatures to reproduce so that their beauty doesn’t vanish when they die. Right now, this man is like a candle burning itself up—feeding on his own good looks and leaving nothing behind. By refusing to pass on his “light,” he creates a kind of starvation in the midst of plenty. The speaker calls him a tender miser, someone who wastes his freshness by locking it away inside himself like a bud that never opens.
The mood is equal parts admiration and exasperation. There’s real tenderness in how the speaker describes the young man as the world’s “fresh ornament,” yet the final couplet swings into a stark warning: either pity the world and reproduce, or you’re a glutton devouring what you owe to the future. It’s intimate, almost scolding, and the sense of urgency makes beauty feel fragile and fleeting.