Lebbe strongly advocated on behalf of the Chinese people against Japanese imperialism. During the Battle of Rehe in 1933, Lebbe led his congregation to rescue and treat wounded soldiers. After the Second Sino-Japanese War broke out in 1937, Lebbe organized and led a Catholic battlefield rescue and relief team which aided wounded soldiers at Taihangshan (太行山) and Zhongtiaoshan (中条山), and led refugee relief efforts, including providing education for students whose schools had been closed by the fighting.