Sebeia (Σεβεια) is known as tsab't (صابئة) by Arabic speakers and is synonymous with what Rabbinic Judaism calls Noahism. In The Hellenistic-Roman world Noahites were called sebeis (σεβείς: Worshippers) while under Islamic Hegemony they were later known as tsabi'un (صابئين) (NB not sabaen سبأيين) making Sabi the best historically attested and widespread term for a multi/non-denominational Noahite. The universal catchphrase for Tsebeia is "La ilahah il Allah". Sources for researchers on non-denominational Tsebeia are not easily available, but sources abound concerning the three major Tsabi denominations, namely dualistic Nasaraeans, proto-scientific Magists, and Herodian Judaizers. Modern "Sabis" are better known in the English-speaking world as Noahites though some still prefer to call themselves Sabi. These "Sabi" words have commonly, though not completely accurately, been translated as "Godfearers" to designate kinds of Quasi-Proselytes.
Thus the word Sabian has been used to refer to a spectrum of believers from a multitude of faiths related to a common souce. Arabic sources describe those who use the Hanif clergy as "Sabiah Hunafa" while others (such as the Harranians) are derogatorily described as Sabiah Mushrikun by both Maimonides and ibn Waḥshiyya. Although "Sabi" groups may share some common concepts or heritage, it is also possible that they refer to completely different groups of people. Sabi'ism is a spectrum from semi-paganism at one end to perfect monotheismat the other. Thus the Harrian Yazdaeans are sabians at one end of the sabian spectrum but it is not the be all and end all of the story. In exactly the same way we have to look at Noahide observance, Sabi'ism is a journey from that end to the enlightened end. At one end of the spectrum Trinitarians have a place according to some authorities, while at the other the student no longer needs to think in such simplistic terms.
Linguistic research has indicated that the word TheoSeBeia is derived from ger ToShaB (גר תושב) and all of these words are supposed to ultimately have the same origin as the Hebrew תושב. For a detailed introduction to this concept please read through the intensive research of Alberto Fratini and Carlo Prato posted at http://www.ricerchefilosofiche.it/.
The Hanif Tsabi is one who has accepted recommendations from the Hunefa such as the adoption of Psalm reading for spiritual nourishment.