There you must stay while worms share you.

As above, “wunien” can also mean ‘live’, or ‘dwell’ – like a home.

That earth-house is loathsome and nasty to live in.

The word “eorð-hus” is an example of a kenning: an Old English compound word which is usually figurative, and emphasises a particular aspect of something. Here, it’s emphasising the similarities between a grave and a house.

You’re firmly locked away there and death has the key.

The personification of death is pretty common in OE poetry: in “The Wanderer”, for example, a wolf shares a corpse “with death”. This line is a reference to the Christian doctrine of the Day of Judgement, which was particularly important to the Anglo-Saxons: at the end of the world, souls will be released from their graves to be judged by Christ. In a sense the line is slightly confused, as while it makes sense for death to lock someone in a grave, releasing them is more the job of Christ.

That house has no door, and it’s dark inside.

As if living in a tiny, smelly house weren’t bad enough, you’re also stuck there. There’s no door, and even if there were it’d be too dark to find it.

dim and dark. That den gets fouler around you.

By calling the grave a “den”, the poet evokes the dens of animals: also in the ground, and usually pretty stinky.

That’s how you’ve got to stay in the cold, cold ground,

We know now that the grave’s going to be pretty small. From here on the poet starts to tell us about all its other delights … starting with the cold.

the roof is built right up against your chest.

Claustrophobia, anyone?

The end walls are low, and so are the side walls;

it’ll be low and level, when you lie in it.

Your house won’t have high ceilings: