The Young Christian Workers (YCW) is an international movement for young Catholics, engaged through a method of education called ‘See, Judge, and Act’. From the 1950s to the 1980s, the Australian YCW became known for running campaigns on a range of social issues and the provision of services – including sporting events and competitions. In this paper, the development of the Australian YCW Football Association during the 1950s is explored, and the history of YCW members’ participation in public debates about the morality of Sunday sport, which culminated in a local referendum in the Melbourne suburb of Camberwell in 1959, is traced. Drawing on archival materials and interviews conducted with former young workers, the paper explores tensions within Christianity around the meaning of ‘leisure’, ‘idleness’, and Sunday as a day of observance and rest. This examination of the Melbourne debate of 1959 will show how religious tensions around Sunday sport were shaped by class, youth, and masculine identities.