I approached them, mistaking the situation for a bright full moon celebration, only to discover it was sadness hidden behind the veneer of festivity.

This couplet is a profound exploration of illusion in love and life. The poet uses the metaphor of 'Purnima' (full moon) to represent perfect, radiant beauty and hope. When he says he went to someone thinking they were the moon, he means he sought pure joy. However, the reality—that they were 'sadness in the guise of light'—tells us that the most deceptive things are often the ones that shine the brightest. It speaks to the pain of misjudgment.