Maaseh Breishit and Maaseh Merkavah

Ma'aseh Breishit (Hebrew: מעשה בראשית) and Ma'aseh Merkavah (מעשה מרכבה), literally "work of Creation" and "work of the Chariot", are terms used in the Talmud for the esoteric doctrine of the universe, or for parts of it.

Ma'aseh Bereshit, following the Genesis creation narrative, comprises the cosmogony of the Talmudic era; Ma'aseh Merkavah, based on the throne-chariot of Ezekiel 1 and other prophetic descriptions of divine manifestations like Isaiah 6, is concerned with the theosophic views of those times.