The Christian left is a range of Christian political and social movements that largely embrace social justice principles and uphold a social doctrine or social gospel based on their interpretation of the teachings of Christianity. Given the inherent diversity in international political thought, the term Christian left can have different meanings and applications in different countries. While there is much overlap, the Christian left is distinct from liberal Christianity, meaning not all Christian leftists are liberal Christians and vice versa.

Christian communism is a theological view that the teachings of Jesus compel Christians to support religious communism. Although there is no universal agreement on the exact dates when communistic ideas and practices in Christianity began, many Christian communists argue that evidence from the Bible suggests that the first Christians, including the Apostles in the New Testament, established their own small communist society in the years following Jesus' death and resurrection. Many advocates of Christian communism and other communists, including Karl Kautsky, argue that it was taught by Jesus and practised by the apostles themselves. This is generally confirmed by historians.