 Sometime vice-president of the assistants' branch of the Teachers' Federation, he organised the Conference on Education for a Progressive Democratic Australia in 1938.A lapsed Jew, Lewis married fellow teacher Ethel Caroline Nelson Teerman on 20 December 1940 at Randwick.In the early 1930s he had joined the Communist Party of Australia, becoming secretary of the Coogee branch, and, using the alias "Samuel Curtis", he was elected to the district committee in 1938.