This is a complex poem so I’ll go through it stanza by stanza to attempt to better understand what her images are doing.
Stanza 1 is the image of a body whose spirit has left (at least) an hour before. The odd thing here is the first word of each of the first two lines, “Delayed”. What is delayed is Death who was “lagging” behind the body just a day before but has now caught up to the victim.
Stanza 2 is unclear but I love the line “a crier of joy” – this is her being clever with the image of crying and grief but also announcing (crier / town crier) joy from the hilltop. So there is joy here and mourning – the images are combined which could speak to the survivor’s grief but also the Christian joy they should feel for leaving to the next world. However, there is also the curious image of the slowness of death – “bliss so slow a pace” – which could mean how slow death moves towards us, but also how slow we move through life (bliss) with death always “lagging” behind. Perhaps that’s why she combines the “crier” and “joy” image since they are so woven together.
Stanza 3 speaks of none who are ever victorious over death and how this “thing” (a body devoid of spirit) will die before it can conquer death because it is frail (hence being “doubtful”). Not even a “king” can outrun death, an image she introduces with the image of the “imperial round” as if it were a king laying in state (the capital rotunda / body on display of a great leader who is dead nonetheless).
She also uses military / war language with “surrendered”, “undefeated”, and “Victory” which has the effect of our lives being a battlefield against death, but it’s a battle with the same outcome every time.