As a Radioman 3rd Class in the U.S. Navy during World War II, Opsahl was sent on an 18 month, top secret, Sino-American Cooperation Organization (SACO) operation in China beginning in early 1944. SACO claims to have accounted for 25,000+ Japanese casualties; five SACO members were lost. Opsahl’s Chinese hosts were the first to inform him that the war was over. For many years, he did not discuss the experiences.
After the war, Opsahl’s adventures helped him decide on a vocation to spread the Bible’s “good news” to the unchurched, like those he had known in China. On June 5, 1952 Opsahl graduated from Concordia Lutheran Seminary in Springfield, Illinois.
After several years in Nebraska, Opsahl planted a mission congregation (St. Paul Lutheran) in Flemington, New Jersey during 1955 and served the parishioners until he retired 35 years later. He had an active post-St. Paul career by preaching and leading worship when and where he was needed in Pennsylvania as well as New Jersey.
On August 28, 1948 Opsahl married Violet Blank in Lakefield, Wisconsin. They raised five boys and one girl. He has 14 grandchildren and 12 great grandchildren.