The speaker proposes that he and the beloved separate so that each can praise the other in verse; absence will be bearable because it allows him to celebrate the beloved through writing.
Lines 1–4 establish a logical paradox that justifies separation. The speaker cannot sing the beloved's 'worth with manners' (proper decorum) because the beloved is 'all the better part' of the speaker. To praise the beloved is to praise himself. Self-praise is vain and indecorous. The solution is separation: distance creates an objective other to whom the speaker can address praise without violating propriety. Paradoxically, splitting the lovers creates the conditions for celebrating their union. This logic is formally elegant but emotionally strained—it suggests that intimacy is compromised by self-regard, that true love requires distance to be properly expressed.
Lines 9–14 refine this: absence is a 'torment,' but it becomes bearable (even sweet) because it grants 'leisure' for contemplation. The speaker fills empty time with 'thoughts of love,' and these thoughts 'deceive' the time sweetly—making hours pass pleasantly through romantic reverie. The final lines claim that the beloved 'teachest how to make one twain'—the beloved teaches the speaker to split himself into two poetic voices, speaker and addressee. The beloved 'remains' absent ('hence remain'), but his absence is exactly what allows the speaker to praise him 'here' in verse. Separation becomes the precondition for literary immortality: only distance allows the lover to become the beloved's eternal poet.
You're in a long-distance relationship, or a friendship that's being separated by circumstance. It hurts, but you realize you can love them differently—through letters, through creating things for them, through celebrating them when you're apart. The distance becomes a way to make the love eternal, to turn it into art instead of just living it day-to-day.