3 Full strongly armed, and on a courser free

Full > Very, exceedingly free > willing, eager (cf. 102.8:4)

4 That through his fierceness foamed all with sweat, 5 And the sharp iron did for anger eat,

sharp > [deliberately] roughened iron > bit

6 When his hot rider spurred his chafed side;

chafed > chafed; heated; angry

7 His look was stern, and seemed still to threaten

stern > fierce, grim still > continually

8 Cruel revenge, which he in heart did hide, 9 And on his shield Sansloy in bloody lines was dyed.

103.34