In the acrostics of his hymns he usually signs his father's name, Kalir. Eleazar's name, home, and time have been the subject of many discussions in modern Jewish literature, and some legends concerning his career have been handed down. It is now assumed that he had lived in Kirjath-sepher in the Land of Israel (Rosh to Brochos Siman 21).
His time has been set at different dates, from as early as the 6th century (basing the view on Saadiah's Sefer ha-galuy), to the end of the 10th century of the common era. Older authorities consider him to have been a teacher of the Mishnah and identify him either with Eleazar b. 'Arak or with Eleazar b. Simeon (See Ma'adanei Yom Tov to Brochos, ch. 5, gloss 5 where he discusses whether he was the son of Rashbi or another Rabbi Shimon). He has been confounded with another poet by the name of Eleazar b. Jacob; and a book by the title of "Kebod Adonai" was ascribed to him by Botarel.
Kalir's hymns early became an object of study and of Kabbalistic exegesis, as his personality was a mystery. It was related that heavenly fire surrounded him when he wrote the "Kedushshah"; that he himself ascended to heaven and there learned from the angels the secret of writing alphabetical hymns; and that his teacher Yannai, jealous of his superior knowledge, placed in his shoe a scorpion, which was the cause of his death.
Modern research points to the probability that he and his teacher were Palestinian Jews; and since Yannai is known to have been one of the halakic authorities of Anan ben David, the alleged founder of Karaism, and must therefore have lived a considerable time earlier than he had, Kalir's time may be fixed with some probability as the second half of the seventh century.
Some beautiful renderings of Kalir's poems may be found in the volumes of Davis & Adler's edition of the German Festival Prayers entitled Service of the Synagogue.
With the awakening of linguistic studies among the Jews and with the growing acquaintance of the latter with Arabic, his linguistic peculiarities were severely criticized (e.g., by Abraham ibn Ezra on Eccl. ch 5, v. 1); but the structure of his hymns remained a model which was followed for centuries after him and which received the name "Kaliric" (). While some of his hymns have been lost, more than 200 of them have been embodied in the Mahzorim, i.e., prayer-books for Rosh HaShanah and Yom Kipur.