Most readers believe Grotius failed to refute Socinus in De satisfactione. This article argues that Grotius’s failure was one of reception rather than argument. It is possible to read De satisfactione as Grotius adverted: a genuine (if subtle) concept of satisfaction, and a defence of the (small-c) catholic faith. Grotius does reject a necessitarian identical satisfaction, in which a repayment is equal to a debt, but like Aquinas, he embraces a teleological equivalent satisfaction, in which a punishment fits a crime. Yet Grotius’s catholic theory was predestined not to persuade a wartime Continental audience whose centre had not held and which sought definitive distinctions from the Roman church. His attempt to forge a broad middle way would succeed only later in Britain.