bounty > goodness, virtue; kindness, generosity great mind > magnanimity
2 The conqueror naught cared him to slay, 3 But, casting wrongs and all revenge behind, 4 More glory thought to give life than decay,
thought > [thought it] decay > death
5 And said, "Paynim, this is your dismal day;
Paynim > Pagan, heathen dismal day > {Dies mali, [one of] the evil or unlucky days of the medieval calendar}
6 Yet if you will renounce your miscreance,
miscreance > false belief, false faith
7 And my true liege man yield yourself for ay,
liege man > {Vassal; faithful follower or subject} ay > ever
8 Life will I grant you for your valiance,