His works include many piyyutim (liturgical poems); his Sefer ha-Roke'ah, a halakhic book; and Sodei Razayya ("Secrets of Secrets") in four parts. The first part of Sodei Razayya is a study of creation (Sod Ma'aseh Bereshit), part of which is an exegesis based on the 22 letters of the Hebrew alphabet in accordance with his belief (derived from the Sefer Yezirah) that the alphabet, the word of God, was the source of existence. The second part of the work, Sod ha-Merkavah ("Secret of the Divine Chariot"), deals with the secrets of angels, the Holy Throne, the Chariot, the Divine Voice which speaks to prophets, the Divine Glory revealed to them, and the ways of revelation and prophecy in general. Sefer ha-Shem ("The Book of the Holy Name"), is mostly devoted to a systematic exegesis of the names of God and, with Hokhmah ha-Nefesh, in which he analysed the various ways by which a connection is established between the soul and the divine world, together make up the third part of Sodei Razayya. The fourth part of Sodei Razayya is a commentary on Sefer Yezirah and contains detailed instructions for the creation of a golem.
Eleazar wrote one other important theological work, Sefer ha-Hokhmah, a major part of which is concerned with exegesis of Holy Names.
It seems that not one of Eleazar's pupils was able to continue his work, especially in the field of esoteric theology.
According to a 13th century story, Eleazar used a cloud to travel from place to place, especially when going to far-away circumcision ceremonies.
Encyclopaedia Judaica, Jerusalem, 1971