Born in Naples, Italy, on 11 July 1892, Rocca immigrated to New York with his parents, Domenico Antonio Rocca and Marietta (Saporito), in 1894. His father had studied for the Catholic priesthood at a seminary in Crotone, but after ordination became disillusioned and left the church to marry. Domenico was received into the Anglican Church in Canada and subsequently into the Episcopal Church in New York in 1907. He began an energetic ministry to Italian Americans in Pennsylvania and Long Island.
Rocca, as his parents' only child, followed his father into the priesthood, attending Lafayette College in Easton, Pennsylvania, with ordination from General Theological Seminary in 1922. He became curate of the Chapel of the Intercession in New York City and married Dorothy Beach there in 1923. Fort Wayne would be his first opportunity to serve as a rector. Upon receiving a telegram from the vestry in October, he preached a trial sermon and was immediately hired, accepting a salary of $250 a month. He arrived in Fort Wayne in November with his wife and widowed mother.
At a time when sharp theological disputes over evolution, the virgin birth, and creationism were dividing the Episcopal Church nationally, Rocca declared his neutrality, asserting his belief in evolution and modern science but also his acceptance of the virgin birth of Jesus, a position that likely made him appear modern and appealing to Trinity's vestry.
The new rector got off on a shaky start in the parish, however, when he ran into conflict with his organist, Fred Church. The organist, who had been accustomed to Father Averill's non-interference in matters of music, found himself at odds with Rocca, who demanded that Church play a more operatic style of music that Church believed his choir boys could not properly sing. On Rocca's first Sunday, Church got up from his organ in the middle of a service and walked out of the building, disgusted with this music Rocca had ordered him to play. At a vestry meeting afterward, Rocca insisted that Church be fired, to which the vestry reluctantly assented. The controversy placed Rocca immediately at odds with Church's many admirers.
Rocca also faced prejudice and ethnic stereotyping of his time. As an Italian American, he felt he had to prove his patriotism by having the hymn "America" played frequently at the services, together with the regular display of the American flag. Three organists were hired in succession, Warren Galbraith, Philip Schick, and in 1925, Joseph Schilling, nicknamed "Prof." All three tried to fill Church's sizable legacy with the boys' choir while accommodating the rector's musical preferences. Rocca used this period to promote the church to young people, speaking at local schools and sending cars around the city to bring them to church on Sunday morning. The missionary focus of the church continued through the 1920s, and many social clubs for men and women continued to meet.
The most significant event of Rocca's rectorate was the redecoration of the nave in 1924. The church interior had grown deteriorated from many years of neglect, but instead of merely refurbishing it, Rocca persuaded the vestry to fund a major redecoration by the New York architectural firm of Bertram Grosvenor Goodhue Associates. The intent was to turn the interior into a replica of a fifteenth-century English oratory. The result was a radical new color scheme that featured dramatic new designs and bold colors of red, blue, gold, and white. The rafters were now painted, as were the pews and most of the other woodwork. The brass was "antiqued" with applique. Some parishioners welcomed the changes, but others were aghast. The cost for the project, $10,000, was added to the existing mortgage of $25,000. By 1926, the total debt of the church had spiraled $40,000, and three years later the stock market crash and the onset of the Great Depression brought a real threat that the bank might foreclose on the church.
In 1931, Rocca decided to obtain a divorce from his estranged wife, which required that he leave the priesthood. In 1932, he married Nellie Wood, the widow of James J. Wood, a wealthy inventor and church member. They were married little more than a year before they, too, divorced. Rocca moved with his mother to Florida and later to Georgia, where he sold insurance. After suffering many financial reversals, he took his own life by hanging himself in 1955.