The Predestination of the Saints/Gift of Perseverance

Moreover, we are admonished that the beginning of men's faith is God's gift, since the apostle signifies this when, in the Epistle to the Colossians, he says, “Continue in prayer, and watch in the same in giving of thanks. Withal praying also for us that God would open unto us the door of His word, to speak the mystery of Christ, for which also I am in bonds, that I may so make it manifest as I ought to speak.” How is the door of His word opened, except when the sense of the hearer is opened so that he may believe, and, having made a beginning of faith, may admit those things which are declared and reasoned, for the purpose of building up wholesome doctrine, lest, by a heart closed through unbelief, he reject and repel those things which are spoken?

Whence, also, he says to the Corinthians: “But I will tarry at Ephesus until Pentecost. For a great and evident door is opened unto me, and there are many adversaries.” What else can be understood here, save that, when the gospel had been first of all preached there by him, many had believed, and there had appeared many adversaries of the same faith, in accordance with that saying of the Lord, “No one comes unto me, unless it were given him of my Father;” and, “To you it is given to know the mysteries of the kingdom of heaven, but to them it is not given”? Therefore, there is an open door in those to whom it is given, but there are many adversaries among those to whom it is not given.