Father Grenon was born in Attleboro, Massachusetts and educated at St. Cecilia School, Pawtucket and Our Lady of Providence Seminary High School and College in Warwick. He completed his seminary studies at St. Bernard’s Seminary in Rochester, New York. Bishop Kenneth A. Angell ordained him on May 12, 1978 in St. Cecilia Church in Pawtucket. He served as assistant pastor at St. James, Manville; as chaplain, Bishop Hendricken High School, Warwick, as pastor at St. Benedict’s, Warwick, Our Lady, Queen of Martyrs, Woonsocket. He also served as deanery vicar for Woonsocket parishes and as chaplain for police departments in Lincoln, Manville and Warwick. Father Grenon was pastor of SS. John & Paul from 2003 - 2018.