1 Faint, weary, sore, emboiled, grieved, burnt,

emboiled > {Boiling with heat; boiling with rage; caused to be boiling with rage: SUS} grieved > hurt

2 With heat, toil, wounds, arms, smart, and inward fire,

smart > acute pain

3 That never man such mischiefs did torment;

mischiefs > misfortunes, evils; injuries

4 Death better were: death did he often desire, 5 But death will never come when needs require. 6 Whom so dismayed, when that his foe beheld,

so dismayed > thus overcome that > [that entity, that dragon]

7 He cast to suffer him no more respire,

He cast > [The dragon] resolved suffer > allow respire > [to] draw breath, live