John Jantzi ya karɓi kiran yin hidima ga Coci na gundumar Shenandoah a matsayin ministan zartarwa na gunduma tun daga ranar 1 ga Agusta. Tun daga shekara ta 2003 ya zama fasto na Cocin Mt. Bethel of the Brothers a Dayton, Va.
A baya can ya yi aiki don Littattafan Zaɓi a matsayin mai ba da shawara na haɓaka / tallace-tallace 1995-2003 kuma a matsayin manajan gunduma na Littattafan Zaɓi na Arewacin Virginia 1981-95. A cikin 2011 ya zama babban malami a Jami'ar Mennonite ta Gabas, yana koyar da tarihin Littafi Mai-Tsarki da jigogin Tsohon Alkawari. Tsawon shekaru tara daga 1980-89, yana cikin tawagar fastoci a Broad Street Mennonite Church a Harrisonburg, Va.
Tun daga 2004 ya kasance mai himma a cikin jagorancin gundumomi, bayan ya yi aiki a hukumar gundumar Shenandoah, a matsayin shugaban hukumar rayarwa, a matsayin memba na Kwamitin Bita na Ofishin Jakadancin gundumar, kuma a matsayin mai koyar da nazarin Littafi Mai Tsarki na Cibiyar Ci gaban Kirista (ACTS). ) tare da daukar matsayin shugaban addini a shekarar 2011.
Yana da digirin digiri na ma'aikatar daga Makarantar Tauhidi ta Union da Makarantar Presbyterian na Ilimin Kirista, babban malamin allahntaka daga Makarantar Mennonite ta Gabas, da digiri na farko na kimiyya a ilimin zamantakewa daga Kwalejin Mennonite ta Gabas.
Shi da iyalinsa suna zaune a Harrisonburg, Va. Ofishin gundumar Shenandoah zai ci gaba da kasancewa a Weyers Cave, Va.