The Protestant churches of Victoria slowly developed a voluntary religious instruction system in State schools following the 'free, compulsory and secular' Education Act of 1872. By the mid 1930s weekly instruction was being provided for some 80 of pupils and this percentage was maintained until the mid 1960s. After 1967, however, the system suffered a rapid and severe decline, especially in postprimary schools. Thomas Luckmann's sociological theory of religious change in the modern world provides an analytical framework for interpreting the changes experienced by Victoria's religious instruction system. It is suggested that though the changes were determined in part by educational developments, at a deeper level they sprang from religious changes in the community. In particular, it is argued that the dramatic slump in religious instruction after 1967 was indicative of a changed status for Protestantism in Victoria.