uhammad wished to send a man named Mu'az to Yaman to receive
some money collected for alms, which he was then to distribute to the poor.
On appointing him he said: "O Mu'az, by what rule will you act?" He
replied, "by the Law of the Quran." "But if you find no direction therein?"
"Then I will act according to the Sunnat of the Prophet." "But what if that
fails?" "Then I will make an Ijtihad and act on that." The Prophet raised
his hands and said, "Praise be to God who guides the messenger of His
Prophet in what He pleases."[22] This is considered a proof of the
authority of Ijtihad for the Prophet clearly sanctioned it.

{18}

When the Prophet was alive men could go to him with their doubts and fears:
an infallible authority was always present ready to give an inspired
direction. The Khalifs who succeeded the Prophet had only to administer the
Law according to the opinions which they knew Muhammad had held. They were
busily engaged in carrying on the work of conquest; they neither attempted
any new legislation, nor did they depart from the practice of him whom they
revered. "In the first days of Islam, the knowledge of the Law was purely
Traditional. In forming their judgments they had no recourse either to
speculation, to private opinion, or to arguments founded upon analogy."[23]
However, as the Empire grew, new conditions of life arose, giving rise to
questions, concerning which Muhammad had given no explicit direction. This
necessitated the use of Ijtihad. During the Khalifates of Abu Bakr, Omar,
Osman and 'Ali--the Khulafa-i-Rashidin, or the Khalifs who could guide men
in the right way, the custom was for the Faithful to consult them as to the
course of action to be pursued under some new development of circumstances;
for they knew as none other did the Prophet's sayings and deeds, they could
recall to their memories a saying or an act from which a decision could be
deduced. In this way all Muslims could feel that in following their
judgments and guidance they were walking in the right path. But after the
death of 'Ali, the fourth Khalif, civil war and hostile factions imperilled
the continuance of the Faith in its purity. At Madina, where Muhammad's
career as a recognised Prophet was best known, devout men commenced to
learn by heart the Quran, the Sunnat, and the analogical judgments
(Ijtihad) of the four Khalifs. These men were looked up to as authorities,
and their decisions were afterwards known as the 'Customs