By “religious thought” we mean that form of thought which is concerned with any of the problems of a religious nature within a particular religion, in the same sense that mathematical thought is the form of thought which deals with mathematical questions and solves mathematical problems.
Needless to say religious thought, like other forms of thought, must have reliable sources from which the raw material of its thought originates and upon which it depends. Similarly, the process of reasoning necessary for the solution of mathematical problems must have a series of established mathematical facts and principles.
The single source upon which the divinely revealed religion of Islam depends and upon which it is based, inasmuch as it is based on a revelation of celestial origin, is none other than the Holy Qur'an.
It is the Qur'an which is the definitive testament of the universal and ever-living prophet hood of the Prophet and it is the content of the Qur'an that bears the substance of the Islamic call. Of course the fact that the Qur'an is alone the source of Islamic religious thought does not eliminate other sources and origins of correct thinking, as will be explained later.
There are three methods of religious thought in Islam. The Holy Qur'an in its teachings points to three paths for Muslims to follow in order to comprehend the purposes of religion and the Islamic sciences:
(1) The path of the external and formal aspect of religion (the Shari'ah):
(2) The path of intellectual understanding; and
(3) The path of spiritual comprehension achieved through sincerity (ikhlas) in obeying God.
These three methods differ from each other in several ways. For instance, since the external forms of religion are verbal expressions in the simplest language, they are in the hands of all people, and everyone benefits from them according to his own capacity.
On the other hand, the other two paths, which are appropriate to a particular group (the elite-khawass), are not common to all. The path of the external forms of religion leads to the understanding of the principles and the obligations of Islam and results in knowledge of the substance of the beliefs and practices of Islam, and of the principles of the Islamic sciences, ethics, and jurisprudence.
This is in contrast to the other two paths. The intellectual path can discover the problems connected with faith, ethics, and the general principles governing practical questions, but the intellectual method cannot discover the specific religious injunctions given in the Qur'an and the Sunnah.
The path of purification of the carnal souls since it leads to the discovery of God given spiritual truths can have neither limits nor measure of its results or of the truths revealed through this divine gift. Men who have reached this knowledge have cut themselves off from everything and forgotten everything but God and are under the direct guidance and dominion of God Himself-May His Name be Glorified. Whatever He wants and not what they want is revealed to them.
We will now take up in detail the three methods of religious thought in Islam.