In Papua New Guinea the German Lutheran mission decided to enact a language policy in the early 1900s sanctioning the use of church languages chosen by the missionaries, instead of developing each local language. In Morobe Province, their policy promoted the development of two local languages, Kâte and Yabem, for use in evangelistic communication. In the 1950s the Lutheran Church changed their language policy and began to replace the use of Kâte and Yabem in church and education with Tok Pisin and English. The early use of Kâte and Yabem within the church domain and the eventual replacement of those languages with Tok Pisin set a precedent for using non-local languages in church services. This paper examines multilingualism in Morobe Province and analyzes how it created a setting open to the acceptance of church languages. The paper also explores the lasting sociolinguistic effects of the Lutheran Church's language policy on eleven people groups the mission encountered. In some cases, the use of Kâte and Yabem in the church domain has had a negative effect on how the people view the validity of their own language in church, while in others the effect has been minimal.