Attar tells a story of the ninth-century Sufi Dhû'l Nûn, who, when trying to heal the grief within his heart, is confronted by the mystic's rigor.
I was wandering in the mountains when I observed a party of afflicted folk gathered together.
"What befell you?" I asked.
"There is a devotee living in a cell here," they answered. "Once every year he comes out and breathes on these people and they are all healed. Then he returns to his cell, and does not emerge again until the following year."
I waited patiently until he came out. I beheld a man pale of cheek, wasted and with sunken eyes. The awe of him caused me to tremble. He looked upon the multitude with compassion. Then he raised his eyes to heaven, and breathed several times upon the afflicted ones. All were healed.
As he was about to retire to his cell, I seized his skirt. "For the love of God," I cried. "You have healed the outward sickness; pray heal the inward sickness."
"Dhû -l-Nûn," he said, gazing at me, "Take your hand from me. The Friend is watching from the zenith of might and majesty. If He sees you clutching to another than He, He will abandon you to that person, and that person to you, and you will each perish at the other's hand."
So saying, he withdrew into his cell.