The poem describes a nightingale who has been singing all day and becomes hungry at nightfall. He spots a glowing glow-worm on the ground and tries to eat it. However, the glow-worm persuades the nightingale not to eat it by pointing out that they were both created by God to beautify the night in their own way, through song and light. Impressed, the nightingale releases the glow-worm and finds food elsewhere. The central message is that all creatures have a purpose and a right to exist without harming one another.