Nyanadassana Mahathera
Bhikkhu Nyānadassana Mahāthera is a Theravāda Greek Buddhist monk, scholar, and teacher.
Early life and education
Bhikkhu Nyānadassana Mahāthera was born Ioannis Tselios in 1959 in Karperi, Serres, Greece, and completed his high school education in Thessaloniki. He studied sociology at the Goethe University in Frankfurt, Germany for two years but left before completing his degree.Ioannis Tselios traveled around South Asia during the 1980s. He first went to India in 1981 and visited key Buddhist sites, including Kushinagar and Lumbini. Later on, he traveled to Sri Lanka.
Monastic life
In 1982, Ioannis Tselios received novice ordination in Sri Lanka at the Polgasduwa Island Hermitage, where he was given the monastic name Nyānadassana, meaning "knowledge and vision." A month later, he renewed his novice ordination at Galduwa, with Kaḍaveddūve Shrī Jinavaṁsa Mahāthera officiating as his preceptor. In 1986, he was fully ordained as a bhikkhu under the same preceptor.For sixteen years, he studied Pali, the Tipiṭaka, and commentarial literature at the Gnānārāma Dharmāyatanaya monastery in Mītirigala. In 1997, he earned the title of Vinayācariya after completing rigorous examinations. Inspired by his teacher, he began teaching the Pāḷi language and the Tipiṭaka for several years.
Meditation
Nyānadassana has devoted decades to meditative practices, including Vipassanā and Samatha. He practised at Nissaraṇa Vanaya in Mītirigala, Sri Lanka, under the guidance of the renowned meditation teacher Venerable Mātara Sri Ñāṇārāma Mahāthera. and spent over three years at the Pa-Auk Meditation Centre in Myanmar, receiving training under Pa-Auk Sayadaw.Between 2008 and 2018, he was regularly invited by Buddhist centres in Singapore, Indonesia, Malaysia, and Taiwan to deliver Dhamma talks and meditation classes. From 2011 to 2019, he resided at Nā Uyana Forest Monastery and International Meditation Centre in Kurunegala, Sri Lanka.
Return to Greece
In 2019, Nyānadassana Mahāthera received an invitation to teach Theravāda Buddhism in Greece from Michail Xynos, who at the time was directing the Theravada Centre for Study and Practice in Greece. From 2019 until 2025, he conducted extensive courses in Buddhist philosophy and psychology in Greek, along with live and online meditation seminars for Greek, Sri Lankan, European, and Asian audiences.During this period, he authored several books.
Publications
Nyānadassana Mahāthera has authored and translated numerous works in multiple languages, including English, German, Greek, and Sinhala. His publications include:Wisdom and the Seventy-Three Kinds of Mundane and Supramundane Knowledge Karaṇīya Metta-sutta — The Message of Peace and Universal Friendliness Ratana Sutta — The Buddha's Discourse on The Three Superb Jewels and Their Intrinsic Power When is Dawn ? When is Dawnrise ? Mode of Veneration of the Buddha Bhikkhu-Pātimokkha — Das Hauptregelwerk der Buddhistischen Mönche Meditation: Liberation or Attachment, The Historical Buddha and His Teaching,;Greek booksΔιαλογισμός: Απελευθέρωση ή Προσκόλληση, Ο Ιστορικός Βούδας και η Διδασκαλία του,
;Greek translationsKaraṇīya Metta-sutta — Το Μήνυμα της Ειρήνης και της Παγκόσμιας Φιλικότητας Αυτά που ο Βούδας Δίδαξε, Dhammapada, Η Σοφή Διδασκαλία του Βούδα σε Στίχους,