Rev. Fr. A. K. Cherian was born to a devout Orthodox Christian family in Pandalam, Kerala, India. Cherian Achen was the youngest child of the Late Koshy Vaidyan and Late Sosamma Koshy. After losing his father at an early age, he often spoke of his fond childhood memories with his mother, three brothers, three sisters and his grandparents. From a young age, Achen was guided by the Hand of God, shaping his journey with wisdom, faith, and purpose.

After completion of high school, he joined NSS College, Pandalam in 1958 and completed his B.Sc. in Mathematics. Achen worked as a teacher in St. Thomas High School, Karthikapally from 1958-1963 and during this time Achen received his B. Ed. from Brunnen College, Tellicherry. Cherian Achen taught in the MGM High School, Thiruvalla and MD Seminary High School, Kottayam (between 1963-1965). In 1965 he enrolled in The Orthodox Theological Seminary, Kottayam, Kerala and completed his G.S.T. and B.D. In 1967, Achen was ordained to the Deaconate by His Holiness Moran Mar Baselios Augen I and was appointed as the Boarding Master in MGM High School and MD Seminary High School. In 1964, he was a founding member of the Bishop Packenham Walsh Teaching and Healing Mission a group comprising of medical doctors, paramedics, and theologians and their purpose was to provide free medical camps in the villages.

Achen was also an active participant in the Orthodox Christian Student Movement holding positions of Auditor and Central Committee member and due to his significant contribution, he was elected as the General Secretary of the Movement between 1968-1970. On July 26, 1971, Achen married Molly Thomas in Mar Elía Cathedral, in Kottayam by H. G. Mathews Mar Athanasios (Late H. H. Mathews I). Subsequently, on August 15, 1971, he was ordained into the Holy Order of Priesthood by His Grace the Late Lamented Daniel Mar Philexinos. Cherian Achen arrived in America in April 1972. He worked hard to organize the Orthodox Christians in and around Bronx, NY and on November 4, 1972, the Bronx parish came into being. The Bronx parish, on its own request, was recognized by The Malankara Orthodox Church in early 1974 and Fr. A. K. Cherian was appointed as the first vicar of the St. Mary's Orthodox Church Bronx (Kalpana #1191 dated 3 March 1974), being the founding father of the Bronx church.

Cherian Achen, a devout and principled leader, dedicated himself to both the spiritual and material growth of the Bronx parish. Although in his belief that a priest should be fully committed to Christ's ministry, he worked as a disbursement accountant at The Reformed Church of America, N.Y. when the parish could not meet his financial needs. Demonstrating extraordinary selflessness, he channeled all his earnings back to the parish, even supplementing them with his own income and for the first ten years he did not take any gifts or remuneration from the parish.

Through Achen's selfless service and strong leadership, he helped the Bronx parish obtain our own church property and built a church honoring the rich traditions of the Orthodox faith, ensuring its architecture and rituals reflected its sacred heritage. Under Cherian Achen's leadership, we were able to expand and construct the St. Gregorios Annex creating a space that fostered the continued growth of the spiritual organizations and the church alike. His dedication extends to the then American Diocese, later becoming the NE American Diocese and the wider church community, where he worked to uphold the traditions of the Indian Orthodox Church for the future generations. He continued his love for learning by receiving a Masters in Science in Education from Fordham University, Bronx, NY in 1977.

He authored five books on the life of "Joseph Rene Vilatte Thimotheos", which was released in 1990, "At the Feet of Jesus", reflections on his journey to the Holy Land released in 2001, "The Sacred Lamps of India", integration of the life of St. Gregorios and Sadhu Sundar Singh released in 2001 (Malayalam) and 2016 (English), "Faith of our Fathers - Holy Faith", released in 2006, and the "Bronx Diary - 1972-2013", released April 2014 (Malayalam) and September 2014 (English).

He faced many challenges but with courage and resilience, he ensured the church remained firmly rooted in the tradition, values, and principles of the Orthodox faith. Cherian Achen was a principled, empathetic, and compassionate priest deeply committed to his faith and practice. He exemplified tenacity in adversities like the loss of his beloved son, Dr. Koshi A. Cherian. He now intercedes with his son, Late Koshikunju, for his wife Molly Kochamma, his children Biju, Sheba, Rekha, Paul Achen, Shallu Kochamma, Nevin and Shoba. His pride and joy are his grandchildren: Leah, Miriam, Abigail, Joanna, Sophia, Nathanael, Olivia, Ethan, and Julia. Go in Peace, Appacha, and pray for us always.