Though made lame by fortune, the speaker finds joy and self-worth through the beloved's virtue, beauty, and success, drawing all his substance from the beloved's shadow.
Line 3's 'made lame by Fortune's dearest spite' is a stunning reversal. Rather than eliciting pity, the speaker's lameness becomes the condition for his spiritual elevation. Like a decrepit father, his physical weakness opens space for another's growth. The laming is not merely tragic but necessary: it creates a kind of blindness to the speaker's own deficiency and a heightened vision of the beloved's worth. Lines 9–12 develop this: the speaker is 'not lame, poor, nor despised' because he has relocated his being into the beloved. He exists as a 'shadow' that receives 'substance' from the beloved's light. This is not loss but transmutation—the speaker's apparent poverty becomes the condition for accessing the beloved's infinite abundance.
Lines 5–8 enumerate all the possible excellences (beauty, birth, wealth, wit) and claim the beloved possesses them all 'or more.' The beloved becomes a kind of perfect human compendium. The speaker then 'engrafts' his love to this 'store'—grafting is a horticultural term, suggesting that the speaker's love grows by being attached to the beloved's stock. Lines 13–14 finalize this: the speaker's only wish is the beloved's continued excellence. The speaker's happiness becomes a function of the beloved's happiness—a complete dissolution of separate interests. This is love as self-oblation: the speaker wishes to exist only as an instrument for the beloved's glory. It is simultaneously beautiful and unsettling, showing how deep love can approach a kind of ego-death.
You're going through a rough patch—job loss, illness, whatever makes you feel like you can't function. But someone you care about is thriving, becoming their best self, and somehow their success becomes your success. Watching them win, seeing them happy, makes you feel alive and complete. Their happiness is your whole world now.