sacred > sacrificial careless > unconcernedly

2 With gilden horns, and flowery garlands crowned

gilden > gilded; golden

3 (Proud of his dying honour and dear bonds,

dying honour > honour in dying (i.e. in being sacrificed) dear > costly; beloved; grievous

4 While the altars fume with frankincense around), 5 All suddenly, with mortal stroke astound,

All > [And all] mortal > lethal, death-dealing astound > stunned

6 Does grovelling fall, and with his streaming gore

grovelling > prostrate

7 Distains the pillars, and the holy ground,