Rev. Mueller was born in Neuenstadt, Linde, Wurttemberg, Germany, in 1827. Orphaned at the age of 10, he was educated in Germany and came to the United States in 1852. He first became acquainted with Bethel during the Synodical Conference held at Bethel in 1863. Then came to Bethel in 1865 to serve the congregation. His bedside manner earned him the love and affection of the Bethel members through some trying times for the nation. In the 1870’s dissent occurred within the congregation, and several families left and organized the United Brethren Church.
In 1869, 5 acres across the road from the church was purchased from Frederick Berkemeier on which the school was built. In 1878 a spacious brick parsonage was erected. Rev. Mueller introduced Easter Sunrise Services at the cemetery.
Rev. Mueller had strength of mind and a strong character, and his imprint on the Bethel congregation was long-lasting. Two of his sons went on to become ministers, serving in Ohio, and two of his daughters married ministers.
Upon leaving Bethel, Rev. Mueller returned to Ohio where he passed away in 1905.
Two ministers were candidates to fill the vacancy of Rev. Mueller — Rev. Anton Philip Frohne and Rev. Schierbaum. Rev. Frohne had grown up in the community and many members were of the opinion that one should not serve in his home church, and therefore, Rev. Schierbaum was chosen. However he became ill and was unable to serve, and Rev. Frohne was elected unanimously.