A native of Chicago, Thiele graduated from Emmanuel Missionary College (which became Andrews University in 1960) in 1918 with a BA degree in ancient languages. After two years of work as home missionary secretary for the East Michigan Conference of Seventh-day Adventists, he left in 1920 for mission service in China. During his 12-year work in China, he was an editor and manager for the Signs of the Times Publishing House in Shanghai.