In Fariduddin Attar's Mosibat Nameh (The Book of Affliction), the tale of Bayazid Bastami and the dog serves as an allegory on the dangers of spiritual pride. When Bayazid draws back his robes to avoid contact with the dog, the animal speaks to teach him that physical impurity is easily cleansed with water and soil, whereas the inner impurity of vanity and self-righteousness remains uncleanable even by a hundred oceans. The narrative emphasizes the Sufi focus on purifying the inner self (batin) and practicing humility over rigid adherence to outward purity (zahir).