spirit of piety and warmth of heart--an attitude reflected in his style, which helped to make his work the most popular moral-religious book in Jewish literature--there is no trace of pantheism or metaphysical mysticism in his nature. His ideas are sane and rational, and their expression clear and transparent. Gabirol's high flights in the "Fons Vitæ" have little in common with Bahya's modest and brief outline of the familiar doctrines of the existence, unity and attributes of God, for which he claims no originality, and which serve merely as the background for his contribution to religious ethics. That Bahya should have taken a few leading notions from the "Fons Vitæ," such as did not antagonize his temperament and mode of thinking, is quite possible, and we shall best explain such resemblances in this manner. As Abraham ibn Ezra in 1156 makes mention of Bahya and his views,[108] we are safe in concluding that the "Duties of the Hearts" was written between 1100 and 1156. As the title of the work indicates, Bahya saw the great significance of a distinction made by Mohammedan theologians and familiar in their ascetic literature, between outward ceremonial or observance, known as "visible wisdom" and "duties of the limbs," and inward intention, attitude and feeling, called "hidden wisdom" and "duties of the hearts."[109] The prophet Isaiah complains that the people are diligent in bringing sacrifices, celebrating the festivals and offering prayer while their hands are full of blood. He informs them that such conduct is an abomination to the Lord, and admonishes them to wash themselves, to make themselves clean, to put away the evil of their deeds from before God's eyes; to cease to do evil; to learn to do well, to seek for justice, to relieve the oppressed, to do justice to the fatherless, to plead for the widow (Isa. 1, 11-17). This is a distinction between duties to God and duties to one's fellow man, between religious ceremony and ethical practice. Saadia makes a further distinction--also found in Arabic theology before him--between those commandments and prohibitions in the Bible which the reason itself approves as right or condemns as wrong--the rational commandments--and those which to the reason seem indifferent, and which revelation alone characterizes as obligatory, permitted or forbidden--the so-called "traditional commandments."