His first post was as a curate in Kettering[5] after which became Vicar of St Mary's, Northampton before further incumbencies at Leicester and Finedon.[6] During the Great War, he served as a Temporary Chaplain to the Forces for 15 months from June, 1917. He had been described at his interview with the Chaplain-General as 'Bright, sane, moderate, A1' and was posted to France. In September, 1918, an 'Excellent Report from BEF about his work and qualifications' was noted.[7] He spent a year at Etaples in charge of the Military Church and 'His ability as a leader of men, his marked power as an organiser .... ‘ were praised.[8] Although far from the front lines, Greaves could remember sheltering from German air-raids, including a 'narrow shave while waiting in a railway station, and a series of temporary sleeping quarters including a tent and a deserted bathing-machine.[9] In September, 1918, he returned to Finedon.