M3:1638 — زین سبب فرمود استثنا کنید / گر خدا خواهد به پیمان بر زنید

This couplet appears in the story of a mountain ascetic who vows to eat only the wild fruit that falls naturally from the trees, never plucking it himself or asking anyone else to do so. For a time, he adheres strictly to his vow. However, Rumi then interjects with this beyt, drawing a general lesson from the ascetic's predicament.

The verse directly references the Quranic injunction (Surah Al-Kahf, 18:23-24) to say "inshallah" (if God wills) when making a promise about the future. Rumi uses this divine command to highlight a fundamental Sufi principle: the impermanence and unreliability of human intention and resolve. Our hearts and minds are constantly shifting, like a feather in the wind or water boiling in a pot, as Rumi explains in the subsequent verses. To make an absolute vow without acknowledging God's overarching will is to set oneself up for potential failure and regret, because we are not masters of our own hearts or of future circumstances. The ascetic's story, therefore, serves as a cautionary tale against overconfidence in one's own will and a reminder of the necessity of humility and reliance on divine providence.