Thus, the ascetics base their approach on spiritual aspiration, while the speculative theologians base theirs on rational inquiry—the faculty of knowledge. Those who follow the straight path need both, and both must accord with what the Messenger brought. For faith consists of words, deeds, and conformity to the Sunnah.

The speculative theologians exalted rational inquiry and turned away from spiritual aspiration. They exalted rational inquiry in general without adhering to inquiry prescribed by revelation. They therefore erred in two respects. First, they failed to give spiritual aspiration its due importance: although they regard outward deeds as obligatory, they do not understand the deeds of the heart or their true nature. Second, in their inquiry they failed to distinguish between true inquiry prescribed by revelation, which the Lawgiver commanded and spoke of, and false, innovated inquiry that is forbidden.

Likewise, the “Sufis” exalted spiritual aspiration in general—the aspiration of the heart—condemned caprice, and went to great lengths in this regard. Yet many of them failed to distinguish between aspiration prescribed by revelation, which accords with the command of Allah and His Messenger, and innovated aspiration. Rather, they devoted themselves to the path of spiritual aspiration instead of the path of rational inquiry, and many of them turned away. Error thus crept in through these two avenues.

For this reason, Christians are drawn to the Sufis, and the Sufis to them, while Jews are drawn to the speculative theologians, and the speculative theologians to them. Between Jews and Christians there is the utmost mutual aversion and hatred. Likewise, between those devoted to speculative theology and opinion-based reasoning and those devoted to Sufism and asceticism