A Dictionary of All Religions and Religious Denominations/Hypsistarii
HYPSISTARII, worshippers of the most high,  a denomination in the fourth century, whose doctrine is reported to have been an assemblage of paganism, judaism and christianity. They adored the most high God with the Christians; but they also revered fire and light with the pagans, and observed the sabbath and the distinction of meats with the jews. They are supposed by some to be a branch of the Massalians.
- Encyclpedia, vol. ix. p. 48.