While Demeter, having taken the form of an old woman called Doso, searched for her lost daughter Persephone, she received a hospitable welcome from Celeus, the King of Eleusis in Attica.
As a gift to Celeus, because of his hospitality, Demeter planned to make Demophon a god by anointing and coating him with ambrosia, breathing gently upon him while holding him in her arms and bosom, and making him immortal by burning his mortal spirit away in the family's hearth every night.
She put him in the fire at night like a firebrand or ember – without the knowledge of his parents: Demeter failed to complete the ritual because Demophon's mother Metanira walked in, saw her son in the fire, and screamed in fright; this angered Demeter, who lamented that foolish mortals do not understand the concept and ritual.
This mock-battle seems to have been the ritual kernel of a whole complex of events known as the Eleusinian Games: Forestalled in making Demophon immortal, Demeter chose to teach Triptolemus (Demophon's elder brother) the art of agriculture; from him the rest of Greece learned to plant and reap crops.
He flew across the land on a dragon-drawn chariot while Demeter and Persephone cared for him and helped him complete his mission of educating the whole of Greece in the art of agriculture.