2 Inflamed with scornful wrath and high disdain,

disdain > anger

3 And, lifting up his dreadful club on high 4 (All armed with ragged snubs and knotty grain),

snubs > snags; stubs (cf. 107.10:7)

5 Him thought at first encounter to have slain. 6 But wise and wary was that noble peer,

peer > {One equally matched with another; nobleman}

7 And, lightly leaping from so monstrous main,

lightly > lightly; quickly so > such main > force

8 Did fair avoid the violence him near; 9 It booted naught to think such thunderbolts to bear.

booted naught to think > [did not bear thinking about]