However...

However, after undergoing a gradual change of meaning, when it came to be used in a different sense by Sunni fuqaha' themselves, it was also adopted by Shi'ite fiqh. Now we shall briefly describe the background of the Sunni usage of this term. 'Ijtihad' in the Sunni Tradition: Sunni scholars narrate a hadith that the Prophet (S), while sending Mu'adh to Yemen, asked him as to on what he would base his judgement.

"In accordance with the Book of Allah", replied Mu'adh, "But what if you don't find it there?" inquired the Prophet (S). "According to the Sunnah of the Apostle of Allah", replied Mu'adh. "But what if you don't find it there too?" asked the Prophet (S) again. 'I will exert my own opinion', replied Mu'adh.

The Prophet (S) put his hand on Mu'adh's chest and said: "Thank God for assisting His Apostle with what he loves." They have narrated other traditions on the subject to the effect that either the Prophet (S) directly commanded his to exercise ijtihad in case they could not find a rule in the Book and the Sunnah, or to the effect that he approved of the practice of his that practised ijtihad. To the Sunnis, this is something definite, confirmed by consensus (ijma').

About the Holy Prophet (S) himself, they have said that some of his injunctions were purely based on personal ijtihad not on revelation. Even in their works on jurisprudence ('ilm al-'usul) the problem is raised whether or not the Prophet (S) could make errors in his personal ijtihad. They have narrated traditions in this regard and transmitted reports of the as to how they justified their own actions or those of others on the basis of ijtihad.

We abstain from quoting any of them here for the sake of brevity. It is evident that in all the above instances the term ijtihad is not used in its current sense, that is, making the utmost effort in deducing rules of the Shari'ah from the related sources (adillah). The meaning of ijtihad there is 'exercising of one's opinion or judgement' (al-'amal bi al-ra'y).

It means that in a case where the Divine dicta are absent or implicit, one should see what would be more acceptable to one's intelligence and taste, or nearer to truth and justice, or analogous to other Islamic laws, and to adopt it for his judgement. Accordingly, ijtihad is also accounted as one of the sources of Islamic legislation, like the Quran and the Sunnah, although not as a source parallel to these two.