 Stein studied at the Quebec Seminary and at Laval University where he studied law and received the Governor General's Academic Medal in 1902.He was admitted to the Quebec bar that same year and became King's Counsel in 1912.Stein practice law in Rivière-du-Loup, Quebec alongside Ernest Lapointe and Léon Casgrain who would both serve as senior cabinet ministers in the federal and provincial governments respectively.