But, before entering on this treatment, it seems to me called for to make one remark on all which I have hitherto written or am hereafter to write, and to draw out distinctly a principle which affects every line of my narrative. This is the necessity of considering the Church as the one kingdom of Christ in all ages: one and the same polity from the Day of Pentecost to the Day of Judgment. This idea has always been before me as the rule of faith in writing the six preceding volumes. It has been the major premiss of my whole argument. To a Catholic the unity of the Church is as necessary as the unity of God; and, equally, to say that the Church is fallible is to deny the existence of any such thing as the kingdom of God upon earth. The sooner that anything which is fallible is swept away the better. The one duty which we owe to fallibility is to label it. The thing called public opinion(1) is fallible, and, accordingly, every generation sweeps it away and substitutes a fresh fallibility, destined to disappear after a similar ascendency, which waxes and wanes in varying durations of time. Division is the strongest proof of fallibility in that which is divided, as unity is of truth in that which remains one mass. For this cause those who substitute national churches in a particular country under the political head of that country, whether king, president, or parliament, for the one divine polity in all countries, are divided from my argument by an impassable gulf. They no more believe in the Church which is “the house of God, the pillar and basis of the truth,” than he who sets up three gods believes in one Infinite Creator and Rewarder of His creatures. The decrees of a General Council in matters of faith are not recognised by them as part of the divine deposit; for to them they are not acts of the Sovereign Lord in His plenary council. The lessons of history fail to convey any definite impressions to minds in which this idea is wanting. Rather the lessons of history affect them as the heathen was affected who heard the description of our Lord’s sufferings undergone for his redemption only to exclaim, “Was it not a long time ago?” There are facts, but no connection. A strong instance of this is that the want of written records in the first three centuries is not made up to them by the acts of the Church in the fourth, fifth, and sixth centuries, because to them the Church is not a polity instinct with one life and following from the beginning identical rules of government. On the contrary, they argue from the silence of perished documents in the three earliest centuries against the recorded practice of the three centuries following. Thus to them the acts of the Church in the Council of Ephesus in 431,(2) the next ecumenical council to the Nicene, throw no light upon the acts of the Church in the Nicene, of which no full record exists. Nor, again, do the acts of the Council of Chalcedon illustrate to them the antecedent