another dish: and if he does partake of it at all, he does so only with reluctance and strain. It may even harm him, or at the very least bring him no benefit, for it is not the nourishment that sustains his body. In the same way, when a servant satisfies part of his need through deeds that are not prescribed, his desire for the prescribed deeds—and the benefit he gains from them—diminishes in proportion to what he has replaced them with. By contrast, whoever channels his appetite and ambition toward what the Law has sanctioned finds his love for it and his advantage from it grow; his religion is perfected and his Islam completed.
Thus you will find that a person who constantly listens to sung odes in the hope of rectifying his heart sees his inclination to listen to the Qur’an wane, until he may even come to dislike it. One who frequently travels to visit tomb-shrines and the like discovers that the love and reverence he holds for the pilgrimage to the Sacred House are no longer what they are in the heart of one content with the Sunnah. Whoever becomes accustomed to drawing wisdom and etiquette from the sayings of the sages of Persia and Rome no longer accords the wisdom and manners of Islam the same standing in his heart. And whoever is engrossed in the stories of kings and their exploits loses his concern for the narratives and lives of the prophets. There are many parallels to this.
For that reason the Prophet—may God’s blessings and peace be upon him—said, “No people ever introduce an innovation without God removing …”