or of hadith, or of tafsir must possess the expertise of a skilled muḥaddith, one who is thoroughly familiar with the hidden defects of reports and the points at which weakness may enter them. If he himself lacks that skill, he should seek the help of those who are experienced and specialized in this noble science.

8 – The notes contain: explanations of unusual vocabulary; identification of places and localities; clarification of the hadith-technical terms employed by the author—such as wajāda, badal, muwāfaqa, and others; brief introductions to certain proponents of Muslim sectarian doctrines; and, in a few instances, critical remarks on passages in which we believe the author was mistaken.

9 – At the beginning of each entry we have placed consecutive numbers for the original biographies in every volume. The numbering ends with the close of each volume, after which the next volume starts anew from one, and so on.

10 – The author used several abbreviations current among hadith scholars. Thus, for ḥaddathanā (“he narrated to us”) he writes thnā, and at times drops the initial thāʾ altogether and leaves only nā; for akhbaranā (“he informed us”) he writes anā or abnā. We have replaced these symbols by writing out the full words.

As for the symbols he used to show which of the compilers of the Six Books narrated from the person under discussion, we have retained them, placing them on the left side of the heading: (ʿ) for all six; (4) for the authors of the four Sunan; (kh) for al-Bukhārī in the Ṣaḥīḥ; (kht) for what he cites in the Ṣaḥīḥ without a full isnād (taʿlīqan); (bkh) for what he records in al-Adab al-Mufrad; (m) for Muslim; (d) for Abū Dāwūd; (t) for al-Tirmidhī; (s) for al-Nasāʾī; and (q) for Ibn Mājah of Qazwīn.

Where any of these symbols occurred within the body of a report, we have removed them and written out the words instead.