The Predestination of the Saints/Gift of Perseverance

We know that in the Epistle to the Philippians the apostle said, “To write the same things to you to me indeed is not grievous but for you it is safe;” yet the same apostle writing to the Galatians when he saw that he had done enough among them of what he regarded as being needful for them, by the ministry of his preaching, said, “For the rest let no man cause me labour,” or as it is read in many codices, “Let no one be troublesome to me.” But although I confess that it causes me trouble that the divine word in which the grace of God is preached (which is absolutely no grace if it is given according to our merits), great and manifest as it is, is not yielded to, nevertheless my dearest sons, Prosper and Hilary, your zeal and brotherly affection— which makes you so reluctant to see any of the brethren in error, as to wish that, after so many books and letters of mine on this subject, I should write again from here— I love more than I can tell, although I do not dare to say that I love it as much as I ought. Wherefore, behold, I write to you again. And although not with you, yet through you I am still doing what I thought I had done sufficiently.