On 30 November 1996, Lucarelli was appointed by
Pope John Paul II as bishop of Rieti; he succeeded
Giuseppe Molinari, previously appointed coadjutor archbishop of
L'Aquila. On 6 January 1997, he received episcopal consecration, in
St. Peter's Basilica in
Vatican City, through the imposition of the hands of the pontiff himself, co-consecrating archbishops
Giovanni Battista Re and
Myroslav Marusyn. On the 2 February, he took possession of the diocese. On 4 December 2002, Lucarelli called the diocesan synod; having concluded the work, and on 2 February 2006 he promulgated the synod book. Lucarelli resigned from his position due to the fact that he had reached the age limit, from the pastoral governance of the diocese of Rieti, which was accepted by Pope Francis on 15 May 2015. He was succeeded by
Domenico Pompili, of the clergy of Anagni-Alatri, until then undersecretary of the Italian Episcopal Conference. He remained apostolic administrator of the diocese until the entry of his successor on 5 September. ==Death==