Theodore Myers Riley (June 9, 1842 - December 1, 1914) was a prominent American Anglo-Catholic priest, author, and seminary professor born in Carlisle, Pennsylvania. A Civil War deserter from the Union Army, he was made a deacon on June 28, 1863, in the Episcopal Diocese of New York. (Riley enlisted on December 31, 1862, in the 151st Infantry Division, mustered on January 5, 1863, and deserted on February 16, 1863.) He was ordained to the priesthood, also in the Diocese of New York, by Bishop Horatio Potter in 1866. He was a graduate of the General Theological Seminary.
He served first as rector of All Saints, Navesink, New Jersey (then called Riceville) in the Episcopal Diocese of New Jersey (1866-1872). He achieved international notoriety as rector of S. Clement's, Philadelphia from 1872 to 1875 during a controversy over ritualism with diocesan bishop the Right Reverend William Bacon Stevens. The bishop demanded that Riley cease wearing vestments unauthorized in the Protestant Episcopal Church, that he refrain from mixing water with the wine in the celebration of the Holy Communion, that he cease elevations during the Prayer of Consecration, that genuflection by choristers and clergy before the altar be discontinued, that there should be no lighted candles unless necessary for illumination, and that the hearing of private confessions be discontinued. With the ritual controversy unresolved, he resigned and was succeeded by Oliver Sherman Prescott of the Society of Saint John the Evangelist; Riley was called to the Church of the Ascension in Chicago, Illinois but declined nomination. He was rector of the former Holy Trinity Church, Minneapolis from 1876 to 1882.
Riley served as Professor of Ecclesiastical History at Nashotah House Theological Seminary (1882-1893), and Professor of Pastoral Theology at the General Theological Seminary in New York (1894-1902). He was chaplain to the sisters of the Community of St. Mary at Kemper Hall in Kenosha, Wisconsin for 13 years concurrent with his tenure at Nashotah House. Blindness forced his retirement from seminary teaching, and he was made an honorary canon of All Saints Cathedral, Milwaukee. He retired as rector of Christ Church, Hudson, New York and was made rector emeritus. He also served briefly as locum tenens at St. Luke's Church, Lebanon, Pennsylvania, and Trinity Church, Muscatine, Iowa.
Riley wrote extensive biographies of seminary dean Eugene Augustus Hoffman and Charles George Gordon (the "Chinese Gordon"), whom he considered an "uncanonized saint."
He was buried in Carlisle, Pennsylvania on December 5, 1914. The Faculty of the General Theological Seminary issued an obituary memorial note dated January 7, 1915: