An Outline of the History of Restriction on Ijtihad
Irshad al-naqqad ila taysir al-ijtihad by al-Sayyid Muhammad ibn Isma`il al-Amir,
I'lam al-mawqa'in 'an rabb al-'alamin by al-Hafiz Ibn al-Qayyim,
Iqaz himam uli al-absar fi al-iqtida' bi sayyid al-muhaijrina wa al-ansar] by al-Fullani, Salih ibn Muhammad (printed),
al-Jannah fi al-uswat al-hasanah bi al-sunnah (which he mentions among his own works),
Dirasat al-labib fi al-uswat al-hasanah bi al-habib by al-`Allamah Muhammad Win al-Sindi,
Muhammad al-adhkiya' by al-Sayyid Ahmad Hasan al-Qannawji,
al-Qawl al-mufid fi hukm al-taqlid, and other books written on ijtihad and taqlid.
Since the books I have mentioned here may be either inaccessible to our Sayyid or he may not have the time to refer to them and find the relevant parts, I shall give here a summary of their contents to the extent of providing a concise answer to the question at hand, leaving the matter of detail to direct reference to the books.
[The Beginnings of Ifta:]
The point on which all the above-mentioned books and historical accounts concur is that after the demise of the Prophet, may peace and God's blessings be upon him and his Household, other Muslims referred to the learned among the Companions and reciters of the Qur'an among them for guidance on the issues of the Shari'ah and acted in accordance with their fatwas, whose basis was either what they had heard from the Prophet, may peace and God's blessings be upon him and his Household, or their own ijtihad, in cases where they had heard nothing from him on an issue. Rather, it has been mentioned in some historical accounts-and al-Maqrizi seems certain about it-that ten among the Companions known as "al-`Asharah al-Mubashsharah" used to practise ijtihad and give fatwas during the lifetime of the Prophet, may peace and God's blessings be upon him and his Household; but as we said earlier this remark is problematic.