Because his work has provoked interest, it has been studied by academics.

The impact of his work is obvious from the range and number of citations by others that are found in academic works, books, postgraduate dissertations, doctoral theses and in very many articles. It is also interesting that academic assignments have been written of which the exclusive subject of research is either the author’s theological work in general, or one specific book by him.

By way of example, it is worth referring here to the article by Tony R. Young, ‘Psychotherapy with Eastern Orthodox Christians’, Handbook of Psychotherapy and Religious Diversity, P. Scott Richards and Allen E. Bergin (eds), American Psychological Association 2014, pp. 89-104, in which Metropolitan Hierotheos Vlachos is described by the author as an Orthodox member of clergy who has made an extensive study of the Fathers, regards Orthodox asceticism as therapy, and has established the term ‘Orthodox Psychotherapy’. Young analyses this specific term on pages 101-102, referring to the author’s books Orthodox Psychotherapy, The Illness and Cure of the Soul in the Orthodox Tradition, and Orthodox Spirituality: A Brief Introduction.

In the same vein, Archbishop Chrysostomos of Etna, who holds a PhD in psychology from the Princeton University, in his work A Guide to Orthodox Psychotherapy: The Science, Theology, and Spiritual Practice behind it and its Clinical Applications, University Press of America 2006, refers in detail to the term ‘Orthodox Psychotherapy’ and notes that the term “… was coined by a gifted religious writer and theologian, Metropolitan Hierotheos Vlachos. …”

About 750 titles of academic works have been identified in which often multiple references are made to the books of Metropolitan Hierotheos. We mention indicatively that one single postgraduate dissertation contains about 300 references.

The publication of his many books and their translation into twenty-seven languages have aroused national and international interest. He has been invited to take part as a speaker in more than five hundred international and national academic conferences, and has delivered a large number of lectures on a wide range of subjects in Greece and abroad.

He also taught at seminars in Canada and the USA. He gave talks on two subjects at the Holy Cross School of Theology, Boston, Archdiocese of America in 1999; he gave three lectures at a Seminar of the Orthodox Church of America (OCA) in Vancouver, Canada (1995) and in Atlanta, USA (1997). He spoke in the central hall of the University of Seattle (1999) at the invitation of the University Senate, and he held, and taught at, a Seminar in Tacoma (Washington State) (1999 and 2007). He spoke at the Pacific Lutheran University of Tacoma (2007). He spoke at conferences and gave lectures organised by the Greek Orthodox Community of St Demetrius in Seattle, USA (1995, 1997, 1999 and 2007) and at an international Conference at the Holy Monastery of St John Chrysostom in Chicago (September 2007). In July 2016 he was the main speaker and gave three lectures at the Clergy Symposium of the Orthodox Church of the Patriarchate of Antioch at the Antiochian Village in Pennsylvania.

In addition, he has spoken in Syria (Damascus, Aleppo, Latakia, Holy Monastery of St George in the Valley of Christians), Lebanon, (Balamand, Koura), Germany, Ukraine, Simferopol in Crimea, Russia (Moscow, St Petersburg, Sergeev Posad), Romania (Bucharest, Iasi, Craiova, Alba Iulia), Bulgaria (Sofia, Varna), Venice, Constantinople, Cyprus (Nicosia, Limassol), England, and elsewhere.

Some of his books are used as textbooks in Theological Schools abroad and in Greece, and are the subject of doctoral theses at universities abroad and of lectures at conferences.

(See catalogue of his Talks and Lectures in and outside Greece)

His research work and his activity as a writer have earned him awards from the Academy of Athens and two University Institutions:

• The Academy of Athens gave an award in 1996 to his book The Person in the Orthodox Tradition (1996), as the best book of the five-year period (1990-1995), following the documented recommendation of the Committee of Academicians, Evangelos Moutsopoulos, Mark Siotis and Metropolitan John (Zizioulas) of Pergamon, at an official event in March 1996.
  (See Evaluation Report and Award)
• The Department of Social Theology of the Theological School of Athens awarded him an honorary doctorate at an official event on 25 September 2008.
  (See event)
• The Department of Medicine of the School of Health Sciences of the University of Ioannina awarded him an honorary doctorate at an official event on 13 March 2016. (See event)

His participation in various International Conferences in Greece and abroad, and the wide-ranging subject-matter of his writings aroused the interest of people outside Greece who were searching for Orthodox theology, which is in dialogue with contemporary challenges, and many of his works began to be translated.

On the initiative of the translators, thirty-three titles of the author’s books (100 translated books) have been translated into twenty-seven languages: English, Arabic, French, German, Spanish, Russian, Serbian, Hungarian, Romanian, Swahili, Chinese, Bulgarian, Ukrainian, Dutch, Albanian, Italian, Finnish, Georgian, Urdu, Korean, Estonian, Indonesian, Portuguese, Polish, Slovak, Latvian and Lithuanian.

The Assistant Professor at the National and Kapodistrian University of Athens, Efthymia Mavromichali, in her article entitled ‘The most influential and widely translated author in the field of Orthodox theology’, writes:

“… If all this writing output of original and translated works undoubtedly makes the Metropolitan of Nafpaktos the most influential and most translated theologian-writer in the field of modern Orthodox theology in Greece, it also places him among the top four most translated Greek writers overall. …”

(See the whole article)
(See the catalogue of his translated writings)