When Pius X High School opened its doors on Oct. 1, 1956, Father Keefe was part of the first sophomore class and graduated in 1959. He followed in his father’s footsteps by attending Creighton University, from which he received a BA in 1963. Shortly after entering Creighton Law School the following year, Father Keefe became very ill with what was thought to be a bad case of the flu that lasted several weeks. He was diagnosed with type I diabetes. This disease was an ever-present consideration and influenced the course of his life, as it was at this time that he made the decision to enter the seminary.

John attended St. Thomas seminary in Denver, Colorado. Beginning on June 14, 1967, he served as a deacon at St. Mary’s Church in Lincoln. Father Keefe was the first priest Bishop Glennon P. Flavin ordained in the diocese, at The Cathedral of the Risen Christ on June 1, 1968. He served first as assistant pastor at St. John the Baptist in Plattsmouth from 1968-1970 and then in several parishes throughout Nebraska, including Cathedral of the Risen Christ from 1970-73 and Blessed Sacrament in Lincoln from 1973-77. In 1977, Father became Pastor of the church of Immaculate Conception of the Blessed Virgin Mary in Rulo, and also served as pastor at parishes in Arago, Prague and Plasi, Aurora and Giltner, and St. Patrick Parish in Lincoln. He taught at Bishop Neumann High School in Wahoo and was senior priest in residence at Sacred Heart Church in Crete. Father Keefe also served as the spiritual director of the Cursillo Movement for four and a half years. Father Keefe spent 10 years serving the diocesan mission in Venezuela, and 10 years serving Cristo Rey Parish in Lincoln, known as “Padre Juan.” The Spanish-language community was formally made a parish during Father Keefe’s tenure.

Father Keefe retired from active ministry in 2013, and lived the last few years of his life at Madonna Rehabilitation Hospital. He passed away at age 82 on October 11, 2023. A Southern Nebraska Register article shared a statement from Bishop Conley made on Oct. 12: Father Keefe was “a great priest with a missionary heart, especially for our Hispanic brothers and sisters.” To benefit Pius X students from Cristo Rey Parish in perpetuity, Fr. Keefe worked with Pius X Foundation in 2011 to establish a scholarship through a planned gift from his estate. The Father John J. Keefe Memorial Scholarship Fund will be used to provide scholarships to assist students from Cristo Rey Parish to attend Pius X High School.