| Sg M | Pl M | Sg F | Pl F | Sg N | Pl N | |
| Nom | þrymfasta (rule) | þrymfastan (rule) | þrymfaste (rule) | þrymfastan (rule) | þrymfaste (rule) | þrymfastan (rule) |
| Acc | þrymfastan (rule) | þrymfastan (rule) | þrymfastan (rule) | þrymfastan (rule) | þrymfaste (rule) | þrymfastan (rule) |
| Gen | þrymfastan (rule) | þrymfæstra (rule) | þrymfastan (rule) | þrymfæstra (rule) | þrymfastan (rule) | þrymfæstra (rule) |
| Dat | þrymfastan (rule) | þrymfastum (rule) | þrymfastan (rule) | þrymfastum (rule) | þrymfastan (rule) | þrymfastum (rule) |
| SgM | PlM | SgF | PlF | SgN | PlN | |
| Nom | þrymfæst | þrymfæste (rule) | þrymfastu (rule) | þrymfasta (rule) | þrymfæst (rule) | þrymfæste (rule) |
| Acc | þrymfæstne (rule) | þrymfæste (rule) | þrymfæste (rule) | þrymfasta (rule) | þrymfæst (rule) | þrymfæste (rule) |
| Gen | þrymfæstes (rule) | þrymfæstra (rule) | þrymfæstre (rule) | þrymfæstra (rule) | þrymfæstes (rule) | þrymfæstra (rule) |
| Dat | þrymfastum (rule) | þrymfastum (rule) | þrymfæstre (rule) | þrymfastum (rule) | þrymfastum (rule) | þrymfastum (rule) |
| Instr | þrymfæste (rule) | þrymfastum (rule) | þrymfæstre (rule) | þrymfastum (rule) | þrymfæste (rule) | þrymfastum (rule) |