In the introduction to the second part of his main work Y.S. delineated the structure and the scope of his historical project, which consisted of two consecutive Hebrew chronicles, spanning a chronology of 1100 years: (1) Sefer Divrei akhamim (The Book Containing the Sayings of the Sages), a historical account from Adam to Rabbanan Savorai (Babylonian Sages of the 7th Century), which is not extant today, and (2) Sefer Divrei Yosef (The Book of Yosef’s Sayings), which was completed on 23 January 1673.

The historical material was cast in Sefer Divrei Yosef into a structure resembling concentric circles. The outermost circle gives a concise description of the politico-religious history of Islam written in a florid, Biblical language. After portraying succinctly the biographies of Islamic rulers beginning with Prophet Muhammad and the first four caliphs (10-40/632-661), followed by the Umayyads, Abbasids, and Fatimids, Y.S. describes in detail the Ottoman rulers, beginning with Osman Beg (r. 699-726/1300-26) up to the reign of Mehmed IV (r. 1058-99/1648-87).

The second circle is a history of the Jews written against this Islamic backdrop, describing the life-stories and activities of Jewish leaders and sages, who lived around the Mediterranean from the 4th/10th to the close of the 11th/17th centuries. The story of the Jewish community in Egypt, and particularly that of Cairo, makes up the third circle, which is a more detailed continuation of the preceding circle, discussing topographical and demographic data, relations between Jews and Muslims, communal institutions, the intellectual achievements of outstanding personages who lived in Egypt (e.g., Maimonides). It is within this third circle where Y.S. documented various calamities, especially episodes of persecution, that befell the Jews of Egypt, and interspersed the scanty autobiographical particulars mentioned above.

Ottoman sultans make up the main topic of about 52 chapters out of the total of 228 of Sefer Divrei Yosef. These chapters dealing with the lives of nineteen sultans supplies the background to the second half of this historical work. Each chapter, dedicated to a certain Ottoman sultan, depicts a significant event or activity that took place during his reign, mostly acts of conquest or critical political vicissitudes. Y.S. elaborates on the careers of prominent sultans, such as Mehmed II (r. 848-50/1444-46 and 855-86/1451-81), Selim I (r. 918-26/1512-20), and Süleyman I (r. 926-74/1520-66), fleshing out the accounts of their military expeditions in a sequence of chapters. The author offers, for instance, much detail on the campaigns against the Safavids (920/1514) and Mamlüks (922-23/1516-17). The detailed presentation of the latter encounter is understandable, since it resulted in the conquest of the Holy Land, which aroused Messianic expectations among the Jews of the Ottoman Empire. Y.S.’s ethnocentric attitude is one of the reasons for his positive evaluation of the Ottomans, whom he describes as “gracious Kings (Malkhey hesed)” or even as “Kings who loved the Jews (ohev ha-Yehudim).” Another expression of the centrality of Egypt in Sefer Divrei Yosef is the enumeration of the names of governors appointed to the province by Ottoman sultans beginning with Selim I up until the reign of İbrahim (r. 1049-58/1640-48). Y.S. occasionally adds short remarks about the relations of Ottoman governors with the local population, and more specifically with the Jewish sarrafbashıs (chief financiers).

Y.S.’s access to the writings of previous historians facilitated his work of reviewing the history of the Ottoman Empire from its early days onward. Y.S. drew mainly on the works of two historians of the 16th century, namely Elia Capsali’s comprehensive history of the Ottoman Empire entitled Seder Eliyahu Zuta and on Samuel Sullam’s Addenda to the Book of Genealogies (Sefer Yuhasin). Among the historical sources Y.S. utilized are also Arabic chronicles, such as Ahmad ibn Zunbul’s Infisal al-awan wa ittisal dawlat Bani Utman. Almost certainly unversed in Turkish, Y.S. had no access to the works of Ottoman historians who wrote in that language. His sketches of the sultans who reigned from the very beginnings of the Ottoman Empire until the middle of the 16th century are an epitome of the works of his predecessors, and lack, therefore, originality. As to the description of the next century, roughly up to 1050/1650, Y.S. did rely on some unidentified informants and on his own experiences, albeit the scarcity of elements of objective source criticism in his Sefer Divrei Yosef marks Y.S. as a faithful follower of the traditions prevailing in medieval Jewish historiography.

A treatise entitled Porath Yosef, which contains Y.S.’s explorations in the text of the Old Testament is extant, but has not been published.