The Hasty Word
There is an English proverb, "Speak of the Devil" [and he will appear]. In this Russian folktale, something very similar happens, and the boy's whole life changes as a result of the words he speaks in haste, summoning the Devil to him.
The story is 1500 words long, so it will take about seven minutes to read, or about fifteen minutes if you read out loud.
Image credit: Painting by Lev Kamenev. Wikimedia.