What Is Faith?

Ultimate Reality it is opposed to the limitations of man; it enlarges his claims and holds out the prospect of nothing less than a direct vision of Reality.
Is it then possible to apply the purely rational method of philosophy to religion? The spirit of philosophy is one of free inquiry. It suspects all authority. Its function is to trace the uncritical assumptions of human thought to their hiding places, and in this pursuit it may finally end in denial or a frank admission of the incapacity of pure reason to reach the Ultimate Reality.
The essence of religion, on the other hand, is faith; and faith, like the bird, sees its ‘trackless way’ unattended by intellect which, in the words of the great mystic poet of Islam, ‘only waylays the living heart of man and robs it of the invisible wealth of life that lies within.’

Muhammad Iqbal - The Reconstruction of Religious Thought in Islam