In Mandaeism, Nidbai (, , sometimes also []) is an uthra (angel or guardian) who serves as one of the two guardian spirits () of Piriawis, the heavenly yardna (river) in the World of Light. In the Ginza Rabba and Qulasta, he is usually mentioned together with Shilmai.
See also List of angels in theology Adathan and Yadathan Xroshtag and Padvaxtag in Manichaeism
References