Yet the spirit of persecution was too repugnant to the spirit of Christ for its triumph to come without a struggle, which can be traced in the writings of the early fathers. Tertullian warmly defends the freedom of conscience; it is irreligious to enforce religion; no one wishes to be venerated unwillingly, so that God may be assumed to desire only the worship which comes from the heart. Still, when the combative energy of the man was aroused in disputation with the Gnostics, it was not difficult for him to find in Deuteronomy and Numbers ample warrant for the maxim that obstinacy is to be conquered, not persuaded. Cyprian says that it is for us to endeavor to become wheat, leaving the tares to God, and he qualifies as sacrilegious presumption the spirit which assumes the function of God in seeking to separate and destroy the tares; yet Cyprian had no hesitation in cutting off from the Church all who differed from him, and consigning them to perdition, which was the only form of persecution at that time within reach. It was, indeed, natural that a persecuted Church should plead for toleration, and the fact that, even in this early period, there should be these flashes of intolerance gives ample warning of what was to come with the power of enforcing dogma on the recalcitrant. Lactantius was the last of the fathers of the persecuted Church, and he could feelingly argue that belief is not to be enjoined by force, that slaughter and piety are in no sense connected, and he boasts that none are coerced into remaining in the Church, for he who lacks piety is useless to God.[186]