Myth, according to the phenomenological standpoint, is a ritual-religious belief. It is a narrative of gods and god-like beings with supernatural powers which is accepted as a fact by many. At a close look on various religious texts we come across myths whose heroes are either prophets as Noah and Solomon, or god-like sovereigns as Yam (JamlJamshid) in Avestan texts which is apparently also the theme of this article. The present article in order of hierarchy, examines Jam's features and functions through the oldest Indo¬Iranian texts (Vedas & Gahan), various parts of the book of A vesta, Pahlavi texts and finally early Islamic _eports. The purpose of this survey is to reveal the traces of the motifs of this old myth left from the old texts into the early Islamic statements and inscriptions in order to show how they are modified and justified through the ages.