From 1984 to 1987, Manetti was a parochial vicar at the Church of Santa Maria in Coverciano [it]. He was then an ecclesiastical assistant at the San Michele youth community until 1995. At the same time, he was ecclesiastical assistant for the youth section of Azione Cattolica. In 1999, he became an ecclesiastical assistant for its adult section. In 1995, Manetti became the pastor of the Church of San Tommaso [it] in Certaldo. He was a religion teacher at the same time.[1]
Manetti took possession of the Diocese of Montepulciano–Chiusi–Pienza on 13 April 2014.[4] As a member of the Tuscan Episcopal Conference [it], he was a delegate for clergy, seminaries, and vocations. As a member of the Italian Episcopal Conference, he was a member of the Episcopal Commission for the Clergy and Consecrated Life and of the Mixed Commission of Bishops - Institutes of Consecrated Life and Societies of Apostolic Life.[1]
Bishop of Fiesole
On 21 April 2022, Pope Francis appointed Manetti to succeed Mario Meini as the Bishop of Fiesole.[1] Manetti took possession of the diocese on 6 July 2022, the feast day of Saint Romulus, the patron saint of Fiesole.[5] On 6 July, the pope also appointed Manetti the apostolic administrator of the Diocese of Montepulciano–Chiusi–Pienza until a new diocesan bishop could be appointed.[6] Manetti remained as apostolic administrator until 3 September 2022, when Augusto Paolo Lojudice took possession as the archbishop-bishop[a] of the diocese.[7]