A great safeguard is the entire faith, the true faith, in which neither anything whatever can be added by anyone nor anything taken away; for, unless faith be one, it is not the faith.
Pope Leo IVirtue is nothing without the trial of temptation, for there is no conflict without an enemy, no victory without strife.
Pope Leo IDavid's Lord was made David's Son, and from the fruit of the promised branch sprang One without fault, the two-fold nature coming together in one Person, that by one and the same conception and birth might spring our Lord Jesus Christ, in Whom was present both true Godhead for the performance of mighty works and true Manhood for the endurance of sufferings.
Pope Leo I