Birch decided to become a missionary when he was eleven years old. After college, he enrolled in
J. Frank Norris' Fundamental Baptist Bible Institute in
Fort Worth, Texas. Norris had visited Shanghai in 1939, two years after the Japanese invasion had started the
Second Sino-Japanese War, and returned full of enthusiasm for "the marvelous opportunity to proclaim Gospel and win souls." Birch, who was eager to finish his studies and had studied many of the topics before, completed the two-year curriculum in one year. He graduated at the head of his class in June 1940 and prepared to join the Shanghai mission of Norris'
World Fundamental Baptist Missionary Fellowship (now the World Baptist Fellowship). When Norris and some 150 members of the church gathered to send Birch and a friend off to China, Norris said they went "fully informed as to the dangers that await them, but they go like the Apostle Paul when he knew that it meant death at Jerusalem." Birch left his family with the words "Goodbye, folks, If we don't meet again on earth, we'll meet in heaven." In July, Birch arrived in Shanghai, which was in
Japanese administered territory, although Americans were considered neutral citizens. While there, he began an intensive study of
Mandarin Chinese. A few months later, he was assigned to
Hangzhou which was also occupied by the Japanese. In October 1941, he left Hangzhou, going by a harrowing foot-trip, narrowly escaping Japanese fire, to run a mission station in
Shangrao, in northwest
Jiangxi. The area was poor and isolated, but Birch reassured his parents that although malaria and
dengue fever had "knocked me down a bit" (weighed 155 pounds/70 kg), he was "coming back up," eating rice and vegetables with Chinese workers, and milk, besides. His Chinese became good enough that he could preach a short sermon. The Japanese
attack on Pearl Harbor in December 1941, added patriotic anger to Birch's outrage at Japanese atrocities in China. He was also finding it harder and harder to survive in Shangrao, and his diet made it harder and harder to maintain his health, already weakened by disease. He may also have started to doubt the mission bureaucrats, who soured him on organized religion. On April 13, 1942, he wrote to the American Military Mission in China saying that for both patriotic and practical reasons he wanted to "jine the Army." He explained that he had been preaching behind Japanese lines for more than a year but was "finding it increasingly hard to do on an empty stomach (no word or funds from home since November)." He wanted to be a chaplain but would cheerfully "'tote' a rifle" or "whatever they tell me to do." ==Wartime work in China==