“In the creation of the heavens and the earth and the alternation of the night and the day, there are surely signs for men of understanding. Those who remember Allāh standing and sitting and (lying) on their sides, and reflect on the creation of the heavens and the earth” (3:190, 191).
The Holy Qur’ān does recognize revelation as a source of knowledge higher than reason, but at the same time admits that the truth of the principles established by revelation may be judged by reason, and hence it is that it repeatedly appeals to reason and denounces those who do not use their reasoning faculty. It also recognizes the necessity of the exercise of judgment in order to arrive at a decision: “But if any news of security or fear comes to them, they spread it abroad. And if they had referred it to the Messenger and to those in authority among them, those of them who can search out the knowledge of it would have known it” (4:83).1
The verse recognizes the principle of the exercise of judgment which is the same as Ijtihād, and though the occasion on which it is mentioned is a particular one, the principle recognized is general.
The exercise of judgment (ijtihād) is recognized in Ḥadīth as the means by which a decision may be arrived at when there is no direction in the Holy Qur’ān or Ḥadīth. The following ḥadīth is regarded as the basis of Ijtihād in Islām: “On being appointed Governor of Yaman, Mu‘ādh was asked by the Holy Prophet as to the rule by which he would abide. He replied “By the law of the Holy Qur’ān.’ ‘But if you do not find any direction therein’, asked the Holy Prophet. ‘Then I will act according to the practice (Sunnah) of the Holy Prophet,’ was the reply. ‘But if you do not find any direction therein,’ he was again asked. ‘Then I will exercise my judgment (ajtahidu) and act on that,’ came the reply. The Holy Prophet raised his hands and said: ‘Praise be to Allāh Who guides the messenger of His Apostle as He pleases’ ” (AD. 23:11). This ḥadīth shows not only that the Holy Prophet approved of the exercise of judgment, but also that his Companions were well aware of the principle, and that reasoning or exercise of judgment by others was freely resorted to when necessary,
1 The original word for the italicized portion is yastanbiṭūn from istinbāṭ which is derived from nabaṭ al-bi’ra, meaning ‘he dug out a well and brought forth water.” The istinbaṭ of the jurist is derived from this, and it signifies the searching out of the hidden meaning by his ijtihād and is the same as istikhrāj, i.e., analogical deduction (TA).