 The view, however, was defended by Hippolytus of Rome, for whom it was essential to say that the Father and the Logos are two distinct "persons" ("prosopa").Some critics of Justin's theology tried to preserve the unity of God by saying that there is no difference to be discerned between the ‘Son’ and the ‘Father’ (unless ‘Son’ is a name for the physical body or humanity of Christ and ‘Father’ a name for the divine Spirit within).This sort of thinking, known as Modal Monarchianism or Sabellianism, would one day lead to a compromise doctrine that the Father and the Son are consubstantial (of the same being).