Although not originally from Rome, the monarchians exerted considerable theological influence in Rome at the close of the 2nd and beginning of the 3rd centuries CE. At the core of monarchian teaching was a strong impulse to preserve the oneness of God against any perceived divisions. Tertullian accuses them of making “a heresy out of the unity [ut et de unico haeresim faciat]”; Tert. Prax. 1.…