Get out the microscope, because we’re going through this poem line-by-line.
Line 5
Tears drown'd one hundred, and sighs blew out two ;
- He compares the next three hundred years to candles or flames that are squelched by the speaker's tears and sighs.
- His tears "drown" the flame of the first 100 years, and his sighs "blew out" the next 200 years like a birthday candle.
- Notice that larger and larger amounts of time are going by, but they seem to vanish in no time at all.
- It's important to note that the speaker is sad because he misses her so much, and maybe he worries that they won't see each other again. (Which returns to our theory that maybe she has died.)
Lines 6-7
A thousand, I did neither think nor do,
Or not divide, all being one thought of you ;
- Time is not just going faster, it's going exponentially faster. Another thousand years go by in the next two lines.
- The speaker is paralyzed and cannot think or act because he is so consumed with the thought of his lover.
- He's basically like moss on a rock for a thousand years – just kind of there.
- Line 7 is probably the most difficult in the poem to puzzle out.
- We think it means that the speaker did "not divide" any part of himself because his entire being was just a single, consistent thought of his love. Independent thoughts and actions – the kind he says he didn't have – would have been examples of such "division."
- He does not divide himself from thoughts of her.
- We guessing that "or not" means the same thing as "nor."
Line 8
Or in a thousand more, forgot that too.
- Boy, this poem is full of awkward, old-fashioned-y syntax.
- After a thousand more years, the speaker forgets even the thoughts of his lover. He's now an inanimate object, it seems.
- But he didn't really forget, did he? After all, he's writing this poem.
- This line is also confusing. This confusion is appropriate and in keeping with the concept that the speaker's brain has been scrambled by his love.
- We see two possibilities here: either he forgets about his lover, or he forgets that he is even having thoughts about his lover, like the way you forget to think of the sky as blue after staring at it for so long that all other colors cease to exist.