Yuz Asaf is the name of two different religious figures of two distinct religious groups.
For the Mandaean Nasaræan Sabeans of Iraq, Yuz Asaf—”Yuz the Gatherer”—was a saint and teacher (in the general gnostic sense of the term) who brought them their religion.
Adherents of the Ahmadiyya Islamic sect of Kashmir identify Yuz Asaf with Jesus of Nazareth, or more precisely, they believe that Jesus is entombed in Srinagar, and that the tomb “is mistaken for that of a prophet named Yuz Asaf” (Kashmiri: युझ असफ, یوذسف).
In Mandaean Sabean tradition
According to oral tradition (preserved in Al-Tabari) of the gnostic Mandaeans, Yuz the Gatherer called his people to the religion (i.e. Mandaeism), which—so the tradition—had been the religion of the Iranian peoples before the coming of Zoroaster.
Gündüz, Sinasi (1994), The Knowledge of Life: The Origins and Early History of the Mandaeans, Supplements to the Journal of Semitic Studies, London: Oxford University Press, p. 31.