Question

What does death'purple altar refer to

Answer 1

Purple is also the color used in funerals. Given that the poem has a religious undertone, as denoted by the term 'alter', the use of the color purplemakes sense. As for the meaning of the line "Upon Death's purple alter now", the line refers to the fact that no one can escape Death.

Answer 2

The altar of the death is purple in color (the altar is stained with blood) also purple is used to describe clotted blood.