In his study of biographical tradition Michael Cooperson argued that prosopographical dictionaries (tabaqat) served as the major means of legitimization for different professional groups through creating a spiritual genealogy going back to the Prophet and/or other luminaries of the early Islamic period. This kind of literary activity had flourished since the first half of the 3rd/9th century CE. After its initial stage the tabaqat tradition persisted almost until modern times in the form of revisions and/or additions (i.e. the dhayl, lit. tail). All major groups had their tabaqats composed in the course of the first two centuries after the inception of this genre. Both religious and "secular" groups were represented; the latter included such groups as poets and even singers. Yet preachers were a very significant exception to that otherwise widespread pattern: they did not have their dictionary written until the late 6th/12th century. Kitab al-qussas wa-'l-mudhakkirin (The Book of [religious] story-tellers and admonishers) was the first book - and probably the only one - that can be classified as a prosopographical dictionary of preachers. Written by Ibn al-Jawzi (d. 597/1201), the famous Hanbali preacher of Baghdad and a prolific writer, this book presented preachers (wu''az) as a coherent group that traces its genealogy back to the Prophet Muhammad himself and has an extremely important mission of molding and honing popular piety. This paper addresses the issue of why this legitimization effort took place so late and offers the following provisional explanation. Madrasas and other waqf-based institutions became part and parcel of the Islamic urban and religious landscape at that period. Offering profitable positions, these institutions gradually brought the process of professionalization of the learned class ('ulama') to its conclusion: the learned eventually abandoned their "secular" occupations. In social terms that meant that there emerged a rather crisp boundary between the learned elite and rank-and-file Muslims. No longer engaged in the same economic activities as other Muslims, the 'ulama' were losing their organic connections with the umma. Under these circumstances Ibn al-Jawzi saw wa'z, or "popular preaching" as it is conventionally rendered by Western scholars, as the major means of restoring and supporting this connection. In doing so he chose to treat preachers (wu''az) as a distinct group that shared an important mission, bringing together Sunni preachers of different legal schools into one group based on a new type of solidarity.