Thunder is goat-drawn: Thor's chariot is pulled by Tanngrisnir and Tanngnjóstr, whose hooves and wheels roll the storm across the sky. Their most useful property is culinary: Thor can slaughter and eat them for supper, and if the bones are laid unbroken on the hides, a touch of Mjölnir at dawn brings them back bleating.
Once, guesting at a farmer's house, Thor shared the meal — and the boy Þjálfi split a leg-bone for the marrow. Next morning one goat limped, the god's knuckles whitened on the hammer, and the terrified family bought peace with their children: Þjálfi and Röskva serve Thor still. Moral, as practical as the myths get: eat what a god serves you exactly the way he tells you to.
The goats that pull the thunder
Snorri introduces the team in Gylfaginning's tour of the gods: Thor owns two he-goats, Tanngrisnir and Tanngnjóstr, and the chariot they draw is how he travels — "and therefore he is called Öku-Þórr," Driving-Thor. Where Odin has the uncanny eight-legged Sleipnir and Freyr a boar of light, Thor — the farmers' god, the common man's god — drives a goat-cart, the humblest rig in the divine motor pool. The choice is exactly right. Goats were the poor homestead's livestock, tough, ill-tempered, and indestructible; and the storm-god's progress overhead, all rumble and clatter, is a heavy cart on a bad road. When thunder rolled, it was possible to say: Thor is driving.
The names keep the animals audibly goats: Tanngrisnir is usually rendered "Teeth-Barer" or "Snarl-Tooth," Tanngnjóstr "Teeth-Grinder" — both built on tönn, "tooth." Anyone who has kept goats knows the sound. The mythology's other famous doublets name cosmic faculties — Thought and Memory, Greedy and Greedy — but Thor's team is named for the noise it makes, which is somehow the most characteristic thing about the entire Thor cult.
The supper at the farmer's house
The goats' great story opens the journey to Útgarða-Loki, and Snorri tells it with the timing of a man who has heard it told well. Thor set out east with Loki, and at evening they came to a farmer's cottage and took lodging. Thor's contribution to the housekeeping was his own team: he slaughtered both goats, skinned them, and set them in the pot, then invited the farmer's whole household to share the meal — instructing them to throw the bones onto the goatskins spread by the hearth. The farmer's son Þjálfi, holding a thigh-bone, split it with his knife to get at the marrow — the one taste of luxury a poor boy at a rich table could not resist.
At dawn Thor raised Mjölnir and hallowed the hides, and the goats stood up alive — but one was lame in a hind leg. Thor noticed. Snorri's description of the god's anger is one of the Prose Edda's great moments of controlled menace: he knit his brows, and his knuckles whitened on the hammer's shaft, and the whole household did what households do in that situation — begged, and offered everything they owned. Thor's wrath passed as quickly as his storms do, and he took a settlement instead of vengeance: the children, Þjálfi and Röskva, who entered his service and follow him still. Then he left the goats behind to heal, and walked on east toward Jötunheimr — which is why the greatest of his adventures, the contests in Útgarða-Loki's hall, were conducted on foot.
Who lamed the goat — Þjálfi or Loki?
Snorri's answer is plain: Þjálfi split the bone. But the Poetic Edda preserves a wrinkle. Hymiskviða, the poem of Thor's cauldron-quest, ends with an aside: the goat of the mountain-driver was half-lame, and the poem lays the mischief at Loki's door — "the cunning one had caused it." Whether this reflects a variant tradition in which Loki engineered the bone-breaking (tempting Þjálfi, perhaps, as some scholars have guessed), or simply a different story altogether, the text is too compressed to settle. The two sources agree on what matters — a lame goat, and a settlement paid in children (Hymiskviða too says Thor got both children of the lava-dweller in payment) — and disagree on whose fault it was. With Loki in the travelling party, the question answers itself in spirit if not in evidence.
Why can the goats be eaten and revived?
The resurrection-meal is one of the oldest ideas the myth preserves. The rule — eat the beast, keep the bones intact, and the god restores it — mirrors a belief attested across northern Eurasia, where hunters and herders returned the unbroken bones of slaughtered animals so they might live again; folklorists have collected the same tale-type from Alpine legend to Sámi tradition. In the mythology's own economy, the goats put Thor's hallowing power on display: Mjölnir is not only a weapon but a consecrating instrument — raised over the pyre of Baldr, over marriage (as Þrymskviða's bridal-blessing shows), and here over dinner, making death reversible where the god's blessing falls. Valhalla runs on the same magic at scale, with the nightly-renewed boar Sæhrímnir. The broken thigh-bone is the fine print made vivid: divine renewal is total, but it is not tolerant. Marrow costs a limp, and the limp costs a family its children.
In the primary sources
The goats' names appear in the Prose Edda — Gylfaginning 21 — and in the name-lists attached to it; the slaughter-and-revival story with Þjálfi's marrow-theft is Gylfaginning 44, prologue to the Útgarða-Loki adventure. In the Poetic Edda, Hymiskviða has Thor lodge his goats with a farmer on the way to Hymir's and closes with the lame goat blamed on Loki and paid for with the farmer's children; Þrymskviða sends the goats hurtling to Jötunheimr with the mountains bursting and earth aflame beneath the chariot. No source records the goats' origin, and their fate at Ragnarök goes unmentioned — presumably they are still harnessed.
Legacy
The goats have outlived most of the pantheon in plain sight. Scandinavian Yule keeps a julbock — the Yule goat of straw and red ribbon that guards Christmas trees across the Nordic countries, most famously the giant Gävle goat erected (and regularly, illegally, burned) in Sweden each December; folklorists trace the custom's roots into the complex of Thor's goats and older midwinter mummery. Tanngrisnir and Tanngnjóstr themselves trot through Marvel's Thor films (as the amiable Toothgnasher and Toothgrinder), video games, and children's retellings, where the eat-them-tonight, drive-them-tomorrow trick remains, as it always was, the best-loved piece of practical magic in the mythology.
Frequently asked questions
What are the names of Thor's goats and what do they mean?
Tanngrisnir and Tanngnjóstr — usually translated "Teeth-Barer" (or "Snarl-Tooth") and "Teeth-Grinder." Both names are built on Old Norse tönn, "tooth," and they are recorded in Snorri's Gylfaginning and the name-lists of the Prose Edda.
How does Thor revive his goats?
He slaughters and cooks them for supper, has the bones thrown onto the spread-out hides, and at dawn hallows the hides with his hammer Mjölnir; the goats stand up alive. The one condition is that the bones be unbroken — when the boy Þjálfi split a thigh-bone for its marrow, the goat rose lame.
Why do Þjálfi and Röskva serve Thor?
As compensation for the lamed goat. When Thor's anger terrified the household, the farmer offered everything he had, and Thor took the two children, Þjálfi and Röskva, as his servants. Þjálfi went on to run against the giant Hugi in Útgarða-Loki's contests.
Did Loki lame Thor's goat?
Snorri says Þjálfi did it by splitting a bone for the marrow. But Hymiskviða, in the Poetic Edda, blames the "cunning" Loki for the goat's lameness. The two attributions cannot be fully reconciled; either the poem knew a variant where Loki engineered the accident, or a different story lies behind the stanza.
Is the Swedish Yule goat connected to Thor?
Folklorists connect the julbock — the straw Yule goat of Scandinavian Christmas — to older midwinter customs with plausible roots in the sphere of Thor's goats, though the chain of transmission is folk tradition rather than documented cult. The Gävle goat is its most famous modern descendant.