On April 23, 1938, he was ordained to the priesthood by Cardinal George Mundelein. Grady studied in Rome for a year before returning to Chicago, where he earned a Master of Arts degree in English from Loyola University in 1944. He taught at Archbishop Quigley Preparatory Seminary and later joined the faculty of St. Mary of the Lake Seminary, serving as procurator. In 1956, he was appointed director of the National Shrine of the Immaculate Conception in Washington, D.C., the largest Catholic church in the United States. As director, Grady oversaw a period of massive construction for the church, assuming his position just as building resumed after a 20-year hiatus. He worked with builders and architects to oversee the cladding of its interior and exterior with limestone and marble, the addition of 26 side chapels, the completion of the "Christ in Majesty" mosaic, and the installation of a massive pipe organ. Shortly after the 1963 assassination of President John F. Kennedy, he celebrated a Mass for President Lyndon B. Johnson using a gold and bejeweled "Texas chalice."
Following the transfer of Bishop William Donald Borders to the Archdiocese of Baltimore, Grady was appointed the second Bishop of Orlando, Florida, on November 11, 1974. He was installed as the second Bishop of the Diocese of Orlando on December 16 of that year. During his 15-year tenure in Orlando, Grady guided the diocese through a period of significant growth. He oversaw the establishment 18 new parishes, a tourism ministry, the San Pedro Spiritual Development Center on the shores of Lake Howell, and a Mission Office to forge a relationship with a sister diocese. This Sister Diocese is the Diocese of San Juan de la Maguana in the Dominican Republic. He expanded ministries to migrants and minorities, founded a scholarship program for African American students, and helped develop apartment buildings for the elderly. He also wrote a weekly column called "The Bishop's Corner" for the Florida Catholic weekly newspaper.
Retirement and death
After reaching the mandatory retirement age of 75, Grady resigned on December 12, 1989. He later died from a kidney ailment at his home in Altamonte Springs, at age 87 on April 21, 2002. Thomas Grady is the great uncle of Kaeleigh Commisso, who says his picture is up in the office at the basilica where he had worked in Orlando, Florida.
