He was ordained deacon on June 27, 1906 by Bishop Arthur Llewellyn Williams of Nebraska and priest on February 10, 1907 by Bishop M. Edward Fawcett of Quincy.[3] He was initially a deacon at St Mary's Church in Oelwein, Iowa, and then became rector of St Mark's Church in Des Moines, Iowa. He also served as rector of Ascension Church in Pueblo, Colorado between 1912 and 1920 and then as rector of All Saints' Church in Omaha, Nebraska from 1920 to 1927.
On June 27, 1906, he married Frances LeBaron Kasson, a descendant of the colonial Massachusetts Governor William Bradford. They had six children: Simon Casady, Frances Cristabel Sherman, Reverend Phineas M. Casady, Reverend Mac Casady, Richard R. Casady, and Thomas Casady Jr.[4]
Episcopacy
Casady was elected by the house of bishops to be the third Missionary Bishop of Oklahoma in June 1927. He was consecrated bishop on October 2, 1927, at All Saints' Church, Omaha, Nebraska by Presiding Bishop John Gardner Murray. When the Diocese of Oklahoma was formed in 1938, Casady became its first diocesan bishop. The Casady School was founded by Bishop Casady and the Episcopal Diocese of Oklahoma in 1947.[5] In 1953, the W. R. Chilton Powell succeeded Casady as bishop of the diocese.[6]