Answer:
I know its death, but age is my answer, and I know its not the popular answer, and I know he talks about death, but I believe age makes a love stronger.
Step-by-step explanation:
He compares himself to a tree in the Autumn: “Upon those boughs which shake against the cold.” He explains that the sun, symbolizing life, in him is fading and the night, symbolizing death, is taking over. These metaphors depict the inevitable aging process of the mortal human being. However, he knows his lover still sees a fire in him but suggests that it will go out soon as the fire is consumed. The speaker knows his lover sees him getting older, but believes it makes their love stronger as they cherish their last moments together before the speaker dies.