- Started study at the technical high school of Waseda University in Tokyo. He took the name Emoto Ryumei while studying in Tokyo. Among his friends were Christians and communists. He met Korean students who supported the independence movement and the exiled Korean government. He studied the Bible. He disciplined himself to endure physical challenges.
- Arrested on suspicion of being a communist because of his communist friends in Japan. He was released after a few weeks of torture.
- March 1 - Birth of son Sung Jin
- June 6 - He leaves his wife and infant son going to Pyongyang, North Korea, teaches there and holds prayer services.
- Moon was arrested on allegations of spying for South Korea and given a five-year sentence to the Hŭngnam labor camp.
- Arrested again and sentenced to five years in a communist labor camp, Heungnam labor camp.