Bel (Chald.). The oldest and mightiest god of Babylonia, one of the earliest trinities,—Anu (q.v.) ; Bel, “Lord of the World”, father of the gods, Creator, and “Lord of the City of Nipur’; and Hea, maker of fate, Lord of the Deep, God of Wisdom and esoteric Knowledge, and “Lord of the city of Eridu”. The wife of Bel, or his female aspect (Sakti), was Belat, or Beltis, “the mother of the great gods”, and the “Lady of the city of Nipur”. The original Bel was also called Enu, Elu and Kaptu (see Chaldean account of Genesis, by G. Smith). His eldest son was the Moon God Sin (whose names were also Ur, Agu and Itu), who was the presiding deity of the city of Ur, called in his honour by one of his names. Now Ur was the place of nativity of Abram (see “Astrology”). In the early Babylonian religion the Moon was, like Soma in India, a male, and the Sun a female deity. And this led almost every nation to great fratricidal wars between the lunar and the solar worshippers—e.g., the contests between the Lunar and the Solar Dynasties, the Chandra and Suryavansa in ancient Aryavarta. Thus we find the same on a smaller scale between the Semitic tribes. Abram and his father Terah are shown migrating from Ur and carrying their lunar god (or its scion) with them ; for Jehovah Elohim or El—another form of Elu—has ever been connected with the moon. It is the Jewish lunar chronology which has led the European “civilized” nations into the greatest blunders and mistakes. Merodach, the son of Hea, became the later Bel and was worshipped at Babylon. His other title, Belas, has a number of symbolical meanings.
Source: H.P.Blavatsky - The Theosophical Glossary