Hayyi Rabbi

Hayyi Rabbi, "the Great Life", is the supreme, ultimately transcendent divine principle of Mandaean theology, the source from which the Lightworld and the whole subsequent chain of divine beings, the uthras, emanate outward, situated at the very summit of Mandaean cosmology above every other named divine figure the tradition recognises.

Jorunn Jacobsen Buckley's study of Mandaean texts and the modern Mandaean community describes Hayyi Rabbi as functioning less like a personal god a worshipper addresses directly with individual petitions and more like the ultimate source and standard of life, light and truth against which the whole of Mandaean cosmology, ritual and ethical teaching is oriented, invoked constantly through the term "Life" itself in Mandaean prayer and ritual formula rather than approached as a distant, separately named deity. Mandaeans, who call themselves Mandayya, "knowers", after manda, gnosis or knowledge, understand correct ritual practice, particularly frequent baptism in flowing water, masbuta, as the primary means of maintaining connection to Hayyi Rabbi and the Lightworld the Great Life represents.

Mandaeism is widely recognised by scholars of religion as the only Gnostic religious tradition from late antiquity to survive as a continuously practised, living faith into the present day, with roots most likely in the region of the lower Euphrates and Tigris, predating Islam and holding John the Baptist, though not Jesus, in high esteem, a distinctive feature that sets it apart from most other traditions that emerged from the same broader late antique Gnostic and baptist religious environment of the Near East. Buckley's scholarship documents that the modern Mandaean community, historically concentrated in Iraq and Iran, has been severely reduced and dispersed by war, persecution and displacement since the late twentieth century, with a large share of the once more substantial community now living in diaspora across Europe, North America, Australia and elsewhere, making the continued transmission of Hayyi Rabbi and the wider Mandaean textual and ritual tradition, still centred on baptism in living water, an urgent and actively ongoing concern for the community's religious specialists and lay members alike rather than a settled, secure inheritance.