In the Nath tradition , Dattatreya is seen as an Avatar or incarnation of the Lord Shiva and as the Adi-Guru ( First Teacher ) of the Adi-Nath sampradaya of the Nathas . In the Nath tradition , Dattatreya is recognized as an Avatar or incarnation of Shiva and as the Adi-Guru ( First Teacher ) of the Adinath Sampradaya of the Nathas .