August 8, 1829 – First Baptist Church (FBC) constituted with seven charter members who desired to establish a faithful Baptist witness in Delphi, Indiana. The first meeting was held in September 1829. The first pastor was A. B. Martin of Sugar Creek, Boone County, followed by Samuel Martin and William Reese.  The church met for several years in a log cabin at the corner of Monroe and Union Streets.
1832 – During William Reese’s pastorate (1832), the county commissioners donated two lots for the congregation to build on, providing a house of worship would be erected within two years. This brick building was finished in about three years. It had a partition down through the middle separating the ladies and gentlemen. The congregation met at this original building for nearly a half century until May 14, 1892.
1892–1895 – During the pastorate of W. T. Van Cleave, the 1835 structure was torn down and the present edifice was built. Building began on March 16, 1892 during which the members rented the I.O.O.F. Hall for services and finally the court room in the County court house until the building was finished enough to resume services. Dedication for the present structure was May 20, 1894. The building cost $9,872.16 to construct and sidewalks were built for $200.00 Mrs. Flora Gross Bradshaw headed a committee to purchase a pipe organ and this was installed around December 25, 1895, at a cost of $800.00. Though most of the original pipes remain intact, it has not been in use since 1945.
1900s–1980s – After the resignation of Dr. Martinson (June 1928), the church doors were closed to the main sanctuary. Due to the efforts of a few faithful members, a small Sunday School was kept going. In November 1930, young college men came to preach until the church called Paul L. Beck as pastor and ordained him on May 26, 1931. He served until January 1934. Those serving as pastor since have been Dwight Dobson, E. M. Cobb, Harold A. Smith, E. A. Ainslie, R. K. Lashley, William Rix, Walter Arrowsmith, J. Franklin Arthur, Paul Mayo, Laurence Dove, William Heinrich, Alfred Smith, and William Glenn, who served from March 1989–December 2022.
In 1973, carpet was laid in the auditorium. In the spring of 1975, the outside of the church building was sand blasted and the bricks were repainted. On Mother’s Day, May 10, 1981, First Baptist dedicated a new Sunday School wing, offices, and fellowship hall connected to the south end of the present church. The mortgage for this new edifice was retired April 1987 and new carpet again laid August 1988.
1990s–Today – On June 14, 1995, the roof of the 103-year-old main structure sustained significant damage from a fire originating from a roofing project. Reconstruction cost to the roof, auditorium, and basement totaled over $400,000.00. The congregation reentered the auditorium for the dedication on June 26, 1996. In March of 2000, the steeple was restored with new roofing slated and aluminum louvers at  a cost of approximately $49,000.00. On October 30, 2022, the congregation called Matthew DelValle to serve as the next vocational pastor upon the retirement of William Glenn.