As per Sanatana Dharma traditions, every Yuga had one foremost Guru, guiding the people on the path of righteousness.
In Krithayuga, it was Bhagavan Sri Sathyadevar; in Threthayugam it was Bhagavan Sri Dattatreyar; in Dwaparayuga it was Bhagavan Sri Veda Vyasar; and in Kaliyuga it is Bhagavan Sri Sankarar.
In our tradition, sannyasis (renunciants) are traditionally categorized into six - Kutichaka, Bahudaka, Hamsa, Paramahamsa, Thuriyadeetha and Avadhuta - each representing a different level of spiritual practice and detachment from worldly life.
Sri Dattatreya is the Adiguru of this sacred Sri Datta Avadhuta Guru Parampara.
The lineage, known from 17th century, is as below:
Sri Sadashiva Brahmendra Saraswati (Neru Adhistanam),
Sri Hariharananda Brahmendra Saraswati,
Sri Omkarananda Brahmendra Saraswati,
Sri Amrutananda Brahmendra Saraswati,
Sri Ramakrishna Brahmendra Saraswatyavadhuta Maha Swamigal,
Sri Sadasiva Brahmendra Saraswatyavadhuta Maha Swamigal,
popularly known as Sri Judge Swamigal
Sri Swayamprakasa Brahmendra Saraswatyavadhuta Maha Swamigal,
popularly known as Sendhamangalam Periyava
Sri Shantananda Brahmendra Saraswatyavadhuta Maha Swamigal
Sri Pravaanundha Brahmendra Saraswatyavadhuta Maha Swamigal