Brother Cletus Joseph was born John Joseph Miggins on April 8, 1924 in New York City to John Joseph and Mary Reen. He attended Ascension School on 108th Street in New York City from 1930-1931 and then Sacred Heart elementary school in the Bronx from 1931-1938. He graduated from De La Salle High School in New York City in 1941 and attended the juniorate at St. Joseph's Normal Institute in Barrytown, New York from 1941-1942. He received the holy habit in 1942. He attended De La Salle College in Washington DC from 1943-1945 and then Catholic University from 1945-1947 when he earned his bacherlor's degree. He then attended graduate school at Manhattan College and earned an master's degree in English in 1957 and subsequent master's degrees in theology and guidance in 1971 and 1972.
He began teaching in 1947 at St. Raphael's in Pawtucket, RI in the subjects of physics, English, religion, French and geometry. In 1952 he was assigned to St. Augustine's in Brooklyn and the following year Bishop Loughlin high school also in Brooklyn. Numerous assignments throughout the 1950s-1980s took him to: St. Bernard's, Lincoln Hall, La Salle Academy, St. Raymond's, St. Joseph's Collegiate, Manhattan College, Sacred Heart and Christian Brothers Academy in Lincroft, NJ.
Brother went by the name "Brother Jack". In 2013, he celebrated his 70th anniversary as a Christian Brother. He died on May 14, 2013 and was buried in St. Gabriel's cemetery in Marlboro, NJ.