	After teaching briefly at the York Academy, Schmucker went on a missionary journey to the western frontier of Kentucky and Ohio. On his return he studied at Princeton Theological Seminary, and was ordained a Lutheran minister (1820). In 1820 he helped to establish the General Synod of the Lutheran Church in America, one of the first organizations of the American Lutheran church. From 1826 to 1864 he served as professor of didactic theology and chairman of the faculty in Gettysburg Seminary, of which he was one of the founders. Schmucker Hall on the campus was named in his honor. During the Battle of Gettysburg, Schmucker's house was used as a field hospital for soldiers of both armies. He was never compensated for the damages incurred.