SEFER HA-YASHAR (Heb. סֵפֶר הַיָּשָׁר; "The Book of Righteousness"), an anonymous work, probably written in the 13th century, one of the most popular ethical books in the Middle
There is also some confusion regarding the nature of the book and the school of ethical concepts to which the author adhered. The style and language conform to contemporaneous philosophical ethical writings and ideas; the author especially made use of Aristotelian terms and concepts. The work, however, is also marked by a tendency to deviate from the central stream of philosophical conventional ethics. This is evidenced in some of the main ideas. The difference is so great that some scholars have concluded that the author might have been a kabbalist who did not want to reveal the full scope of his mystical beliefs. Some ideas in the work also bear great similarity to the ethical concepts of the Ashkenazi ḥasidic movement which reached its peak in the 13th century, and especially to *Sefer ha-Ḥayyim, which was written by one of the *Ḥasidei Ashkenaz.
Most of the unusual ideas are found in the first part of the work which describes the creation and explains why the wicked were created together with the righteous. The rest of the work is concerned, in a rather conventional way, with the main themes of Jewish ethics: love and fear of God, repentance, prayer, and good deeds. In several editions there are variations in the arrangement of the chapters and even in the content. No critical edition of this work has been published, and until the correct text is ascertained, the problems concerning the authorship and the underlying philosophic thought cannot be solved satisfactorily.
I. Tishby, Mishnat ha-Zohar, 2 (1961), 657–8 n. 12; J.M. Toledano, in: HḤY, 11 (1927), 239; G. Vajda, L'Amour de Dieu dans la théologie juive du moyen âge (1957), 181 n. 1; G. Scholem, Ursprung und Anfaenge der Kabbala (1962), 94–96.