Jewish Combat Organization
Lazarus was a career officer forced out of the military by the Vichy laws on the status of Jews, a series of antisemitic laws passed by the Vichy government in 1940–1941. He joined the Armée juive (Jewish Army), a Jewish resistance group that later became the Organisation Juive de Combat (Jewish Combat Organization). At first, he instructed youth in the region of Grenoble in basic military skills. Then, he was charged with overseeing autonomous Armée juive maquis guerillas in the Tarn department.