V. 10. _Wherefore, dear brethren, give so much the more diligence to make your calling and election sure._ The election and eternal foreknowledge of God is indeed in itself sure enough, so that man does not need to make that sure. The calling is also effectual and sure. For whoever hears the Gospel, and believes thereon, and is baptized, he is called and saved. Since we then are also thereunto called, we should apply so much diligence (says Peter), that our calling and election may be assured with us also, and not only with God. This is now such a mode of scriptural expression as St. Paul uses, Eph. ii., "Ye were strangers to the covenant of promise, so that ye had no hope and were without God in the world." For although there is no man, neither bad nor good, over whom God does not reign, since all creatures are His, yet Paul says he has no God who does not know, love, and trust Him, although he had his being in God Himself. So here, also; although the calling and election are effectual enough in themselves, yet with you it is not yet effectual and assured, since you are not yet certain that it includes you. Therefore St. Peter would have us make such calling and election sure, by good works. Thus you see what this Apostle attributes to the fruits of faith. Although they are due to our neighbor, that he may be benefited by them, still the fruit is not to be wanting, that faith may thereby become stronger, and do more and more of good works. Besides, this is quite another kind of power from that of the body, for that grows weary and wastes away if it is used and urged somewhat too far: but as to this spiritual power, the more it is used and urged, the stronger it becomes; and it suffers injury if it is not exercised. For this reason did God introduce Christianity at the first in such a manner as He did, driven and tried by the wrestling of faith, in shame, death, and bloodshed, that it might become truly strong and mighty, and that the more it was oppressed the more it might rise above it. This is St. Peter's meaning in this place, that we should not let faith rust and lie still, since it is so ordained that it is ever made more and more strong by trial and exercise, until it is assured of its calling and election, and cannot fail.