Rev. Karl Samuel Kleppisch was installed as Holy Cross' fourth pastor in May 1866. He served as pastor for Wartburg and St. Joe-Renault while also teaching at the school. Minutes from voter's meetings in 1868 indicate that Rev. Kleppisch preached an English service in Red Bud once a month.

The new school was built in 1867, costing $750. This building was used until 1929.

The pastor was relieved from his teaching duties when Heinrich Johanning, a member of the congregation, was nominated to teach from January to May 1868.

Charlotte Johanning began teaching at Wartburg in the fall of 1868, being paid $15/month for her services. Children who were not members of the congregation were charged a $0.75/month tuition. There is no indication when she stopped teaching, but a Fraulein Johanning was still paid a salary in 1871. In 1890 the tuition for non-members was dropped to $0.35/month.

Kleppisch received a call to Belleville in July 1871. August 1871 saw the arrival of Rev. Johann Nachtigall. He was the third and final pastor to serve both Holy Cross, Wartburg and Holy Cross, Renault.

Nachtigall attended Steeden Proseminary in Hesse-Nassau, Germany, and graduated from Concordia Seminary in 1871. He was ordained at Wartburg on September 10, 1871 by Rev. F. Schaller.

Heinrich Keller came to teach in 1874 and taught there until 1881.

When the church was built in 1863, there was no bell tower. A wooden tower was added in 1874.

A call for a teacher to serve as organist also was extended in August 1881. The call offered a salary of $25/month, a house for the family, firewood for heat and a garden near the house. He would also receive gifts of meats and vegetables from members. It also allowed for $30 in moving expenses. This call was sent to Heinrich Johanning, who accepted it in September 1881. He began teaching in October after a thirteen year absence.

In 1883 a new house for the resident teacher was constructed at a cost of $467.89. This house was the residence for teachers and church sextons until 1964. When the house was not required for either, it was rented out. Such was the case when Henry T. Buettner and his family moved from St. Louis to Wartburg. Congregational teachers who resided in this house were: Heinrich Johanning, Herman Rengstorf and Theodore Scheiwe. Beginning in 1949, teachers were provided living arrangements elsewhere.

The teacherage was used for Sunday School classes from 1966 to October 1990. At that time classes were moved to the new addition of the 1929 school building.

On June 13, 1884, two readers, H. Hahn and L.P. Buettner, were appointed by the voter's assembly. Their duty was to hold reading services in the pastor's absence or during a vacancy. Sometimes the pastor would preach at neighboring churches for special services. In this instance or in the instance of an illness, the reader would conduct the service. At the same time, L.P. Buettner and Fred Boehne were appointed as song leaders to start the congregational hymn in case the organist was absent. Henry T. Buettner was appointed song leader in 1889 and also served as a reader until 1917.

The present policy of quarterly voter's meetings has been in effect since February 1885. Before this change, voter's meetings were held monthly.

Nachtigall left Holy Cross in 1885 after a fourteen-year pastorate.