Recourse to Rome as the oracle of the faith was so obvious an expedient, given the prevailing attitude towards tradition, that we can only be surprised to find how slow and gradual was the triumph of the Roman claims. The victory of logic was retarded both by the pride and by the common sense of the other Western Churches. On the one hand, the See of Carthage clung to the old ideal of Christendom as a confederation of self-governing churches, which might consult one another as they pleased but recognised no superior except a general council. Carthage carried with her the whole Church of Africa, and furnished an example which less illustrious communities were proud to imitate. The conquest of Africa by the Vandal heretics was necessary before the African Christians would consent to look to Rome as their spiritual metropolis. On the other hand, the rulings of the Roman bishops were justly suspected of being tempered by regard for expediency. Sometimes they relaxed penitential discipline, for fear of driving the weaker brethren to apostasy. Sometimes, under pressure from Constantinople, they proposed an ambiguous compromise with heresy. Such considerations were but gradually overborne by the pressure of circumstances. The spread of Arianism and the irruption of the Teutons (themselves often Arians) at length compelled the churches to take the obvious means of preserving their imperilled uniformity and union. It is in the acts of the Council of Sardica (343 A.D.) that we find the first explicit recognition of the Pope as an arbiter and (we may almost say) a judge of appeal. This council was merely a gathering of Western bishops, and the canons which it passed were never accepted by the Church of Africa. So doubtful was their validity that the Popes of the next generation disingenuously asserted that they had been passed at the earlier and more famous Council of Nicaea (325). Yet even at Sardica the Pope was only endowed with one definite prerogative. Henceforward any bishop condemned by a provincial synod might appeal to him; he could then order a second trial to be held, and could send his legates to sit among the judges; but he could not hear the case in his own court. More striking than this decree are the words of the letter which the Council addressed to Pope Julius: "It will be very right and fitting for the priests of the Lord, from every province, to refer to their Head, that is to the See of Peter." This recommendation was readily obeyed by the Churches of Gaul and Spain. Questions from their bishops poured in upon the Popes, who began to give their decisions in the form of open letters, and to claim for these letters the binding force of law. Pope Liberius (352-366 A.D.) appears to have commenced the practice, although the earliest of the extant "Decretals" is from the pen of Pope Siricius (385). Sixty years after Siricius' time, when the Western Empire was in its death-agony, this claim to legislative power was formally confirmed