József Eugene Slaboda was born in 1914 in Trenton, New Jersey, to Joseph Slaboda and Barbara Bumbera. His family was Greek Catholic. Among his siblings, Anna Slaboda joined the women’s branch of the Order of St. Basil the Great, where she was known as Sister Romayne; her later obituary specifically mentions Rev. Joseph Slaboda among her deceased siblings. This family connection is also supported by genealogical records.

He completed his theological studies at St. Procopius College. The exact date of his ordination is currently unknown, but he began his priestly ministry as early as the late 1930s. According to the data uncovered so far, he served in Wilkes-Barre around 1939, and in 1940 he was the pastor of Holy Trinity Byzantine Catholic Church in Sykesville, Pennsylvania. The parish’s own historical roster lists Rev. Joseph Slaboda by name for 1940, immediately between Joseph Kovalchik and Eugene Ustie.

His later posts included Bridgeport, Mont Clare, Coatesville, and Pottstown. He served in Pennsylvania for an extended period, and the final years of his life were also spent in Mont Clare. According to earlier biographical information, he suffered a heart attack on Christmas Day 1975 and died on January 19, 1976, as a result of a second heart attack.