From Bell’s History of Northumberland County 1891: It has been stated that the first religious services in the immediate vicinity of Milton of which there is any record were held by a Reformed minister. This denomination was early represented among the German element, and although there is no record of the organization it was doubtless among the first religious bodies that secured regular pastoral services. The school house on Lower Market street was the first place of worship. In 1807, uniting with the Lutherans, a small one-story log house on the south side of Mahoning street was purchased for school and church purposes, and here the Rev. Justus Henry Fries and other early Reformed preachers conducted worship and administered the Sacraments agreeably to the usages of their church.
In 1817, neither the Presbyterian, Reformed, or Lutheran congregations being strong enough numerically or financially to undertake the erection of a church edifice individually, they united in the construction of a union church building near the foot of the hill at the eastern end of Mahoning street. In this movement Daniel R. Bright was the leading spirit; associated with him as building trustees were Adam Follmer and Adam Gundekunst, and under their supervision the carpenter work was done by Conrad Henry, and the stone and brick work by James Shearer and John Snyder. The corner-stone was laid, October 5, 1817, by the Reverends Hood, Repass, and Fries, in the presence of Lutheran, Reformed, and Presbyterian people. The work did not progress very rapidly, however, and it was not until the 23d and 24th of May, (Sunday and Monday), 1819, that Harmony church was dedicated. At that time the Reformed congregation was fully organized with Christian Markle as elder and Joseph Rhoads as deacon, and Mr. Fries became its regularly installed pastor. As thus completed, Harmony church was a large two-story brick edifice, fronting toward the west, and surmounted by a cupola and bell. Spacious galleries extended around three sides of the church; the pulpit was at the east side, made of beautiful carved work, and elevated considerably. There were four entrances, two on the west and one each on the north and south. The completion of so expensive a work of architecture as this was considered at that day left the joint owners a debt of several thousand dollars, for the liquidation of which resort was had to a lottery. The tickets were sold at three dollars; but from various causes the necessary amount was not realized. This was in 1822, and in the month of June of that year, while the lottery scheme was being energetically pushed, a singular natural phenomenon occurred. On the afternoon of a clear day a small cloud was observed to rise in the west; it crossed above the town, and without any of the other accompaniments of a storm a single flash of lightning struck the steeple of Harmony church, tearing a crooked furrow in the plastering of the southeast side from the ceiling to the floor. This was regarded by many as an indication of divine displeasure at the discord then prevailing among the three churches, and disapproval of the methods resorted to in raising money. At all events, the lottery was abandoned; the Lutheran and Reformed churches paid the debt in 1827, and instituted civil proceedings to compel the Presbyterians to contribute their share, obtaining judgment in the sum of one thousand two hundred sixty-two dollars. On the 27th of January, 1831, the interest of the Presbyterians was sold at sheriff's sale and purchased by Adam Follmer for eight hundred dollars. The Reformed and Lutheran congregations thus secured exclusive possession, and for nearly a score of years were the joint occupants of the church, during which period the name was somewhat more appropriate than during its previous history. In 1850 the Lutherans withdrew, and from that date the Reformed congregation owned and occupied the church individually until 1866.
At a congregational meeting in January, 1866, the desire for the erection of a new church edifice was formally expressed by the appointment of a building committee composed of Levi Truckenmiller, William H. Frymire, J. M. Follmer, Charles Newhard, Aaron Reber, John Houtz, and Jacob Houtz. The consistory at that time consisted of William H. Frymire, Charles Newhard, Jacob M. Follmer, and Levi Balliet, elders; deacons: John J. Fansnaught, William D. Snyder, Simon Gheris, and Aaron Reber. The corner-stone was laid, May 17, 1866, and the dedication occurred on the 18th of November following. The materials of the old church were largely utilized, and the new building, two stories high and constructed of brick, occupied the same site as the present place of worship on the west side of Arch street above Broadway. It was destroyed in the fire of May 14, 1880. July 24, 1881, the corner-stone of a new church was laid; Charles Newhard, Israel Scott, Levi Balliet, John Houtz, Peter Rangier, and Rev. S. B. Schafer, the pastor, constituted the building committee. This edifice was completed in due time, but owing to defective construction it was removed in 1887. The corner-stone of the present church was laid on the 4th of September, 1887, and the basement was used for the first time on the first Sunday in May, 1888. This is a handsome brick structure with a seating capacity of eight hundred, and cost seventeen thousand dollars. The Rev. Justus Henry Fries continued to serve this church as pastor until 1823. He was followed by Samuel Gutelius, 1824-27; Henry Wagner, 1827-35; Daniel Gring, 1835-46; Ephraim Kieffer, English colleague to Mr. Gring, 1840- 44, followed by Henry Harbaugh, 1844-46, when he succeeded to the pastorate entirely and remained until 1849; Edwin M. Long, 1840-52; Albert G. Dole, 1853-65; Samuel H. Reid, 1866-73; F. F. Bahner, 1873-77; S. B. Schafer, 1878-82; F. C. Yost, 1883-89; D. W. Ebbert, 1890, present pastor.