Ibn Jau, Jacob
IBN JAU, JACOB
IBN JAU, JACOB (d.c. 990), wealthy silk merchant and manufacturer, and nasi (leader) of the Jews in Muslim Spain (including parts of Morocco) after the death of *Ḥisdai ibn Shaprut of Cordoba. The source of information on Jacob ibn Jau and his brother Joseph is the Sefer-ha-Kabbalah by Abraham ibn Daud. Residents of Cordoba, the Ibn Jau brothers sought the favor of al-Mansūr, chamberlain to the caliph Hishām ii, and virtual ruler of Muslim Spain, and presented a gift of gold and luxurious silk clothing to al-Manṣūr, thereby impressing him with their wealth and prestige. Al-Manẓūr appointed Jacob nasi of Jewry throughout the kingdom, and Cordoba Jewry made the office a hereditary position for Jacob's descendants. However, when one year later Jacob failed to produce the sum of money in taxes demanded of the Jews by al-Manẓūr, the latter had him imprisoned. After serving a year's sentence, Jacob was released by Hishām ii, who reinstated him as nasi.
Ibn Jau is particularly noted for his vigorous support of Joseph *Ibn Abitur and his equally vehement opposition to Ḥanokh, head of the academy of Cordoba, regarding rabbinical authority. Ibn Jau attempted to give the control of religious matters to Ibn Abitur while he was in charge of fiscal matters. Ibn Daud states that during Ibn Jau's first year as nasi, he threatened Hanokh with violence should he render judicial decisions. Even after his reinstatement, Ibn Jau was neither successful in undermining Ḥanokh's authority nor in removing him from his position of head of the academy. Despite his personal ambition and obsequiousness to Muslim authorities, Ibn Jau was remembered for his generosity to the poor, and was mourned by Ḥanokh who expressed his concern for the welfare of the poor at the loss of their benefactor.
G.D. Cohen, in: paajr, 29 (1961), 55–123; Abraham Ibn Daud, Sefer ha-Qabbalah – The Book of Tradition, ed. by G.D. Cohen (1967), 68–70; Ashtor, Korot, 1 (1966), 245ff.; Baron, Social, 5 (1957), 44f.