As the Founder & General overseer of Gospel Herald Ministries, Dr. Rumishaeli is a highly esteemed and seasoned Pastor and Teacher as well as an excellent mentor. He has ministered to different communities in Tanzania for over 25 years since he got his calling to take the good news of Jesus to the lost, during the course of his work, he and his wife, Hon. Dr. Esther Lyimo have overseen the establishment of an orphanage, planting of churches in the village communities and construction of water wells and fish ponds in places that needed them the most. His achievements in this ministry has seen him being honored by many whilst remaining humble and always having a pioneering spirit.

He is currently residing in Arusha and hard at work in construction of GHM headquarter buildings, giving Bible teachings in collaboration with Breakthrough International Bible University (BIBU) and also supervising the Kirya Missions Project.