In Fariduddin Attar's Conference of the Birds, the tale of a man who asks the Prophet for a prayer rug to avoid the burning sand serves as a profound allegory for spiritual suffering and sincerity. The Prophet refuses the request, explaining that a spiritually wounded soul requires a 'brand' (daagh), much like cauterizing a physical wound. By placing his face directly on the hot earth during prostration, the seeker physically manifests his internal spiritual pain. This metaphor suggests that enduring hardship in worship is a necessary mark of genuine devotion, allowing true seekers to be recognized by the metaphorical brand on their hearts.