2 Peter 3:1-4
1. This second epistle, beloved, I now write unto you; in both which I stir up your pure minds by way of remembrance:
1. Hane jam, dilecti, secundam vobis scribo epistolam, in quibus excito per commonefactionem vestram puram mentem;
2. That ye may be mindful of the words which were spoken before by the holy prophets, and of the commandment of us the apostles of the Lord and Saviour:
2. Ut memores sitis verborum quae predicta sunt a sanctis prophetis, et praecepti nostri, qui sumus apostoli Domini et Servatoris;
3. Knowing this first, that there shall come in the last days scoffers, walking after their own lusts,
3. Hoc primum scientes, quòd venient in extremo dierum illusores, secundum suas ipsorum concupiscentias ambulantes,
4. And saying, Where is the promise of his coming? for since the fathers fell asleep, all things continue as they were from the beginning of the creation.
4. Ac dicentes, Ubi est promissio adventus ejus? Ex quo enim patres dormierunt, omnia sic permanent ab initio creationis.
1. Lest they should be wearied with the Second Epistle as though the first was sufficient, he says that it was not written in vain, because they stood in need of being often stirred up. To make this more evident, he shews that they could not be beyond danger, except they were well fortified, because they would have to contend with desperate men, who would not only corrupt the purity of the faith, by false opinions, but do what they could to subvert entirely the whole faith.
By saying, I stir up your pure mind, he means the same as though he had said, "I wish to awaken you to a sincerity of mind." And the words ought to be thus explained, "I stir up your mind that it may be pure and bright." For the meaning is, that the minds of the godly become dim, and as it were contract rust, when admonitions cease. But we also hence learn, that men even endued with learning, become, in a manner, drowsy, except they are stirred up by constant warnings. 
It now appears what is the use of admonitions, and how necessary they are; for the sloth of the flesh smothers the truth once received, and renders it inefficient, except the goads of warnings come to its aid. It is not then enough, that men should be taught to know what they ought to be, but there is need of godly teachers, to do this second part, deeply to impress the truth on the memory of their hearers. And as men are, by nature, for the most part, fond of novelty and thus inclined to be fastidious, it is useful for us to bear in mind what Peter says, so that we may not only willingly suffer ourselves to be admonished by others, but that every one may also exercise himself in calling to mind continually the truth, so that our minds may become resplendent with the pure and clear knowledge of it.
2. That ye may be mindful. By these words he intimates that we have enough in the writings of the prophets, and in the gospel, to stir us up, provided we be as diligent as it behoves us, in meditating on them; and that our minds sometimes contract a rust, or become bedimmed through darkness, is owing to our sloth. That God may then continually shine upon us, we must devote ourselves to that study: let our faith at the same time acquiesce in witnesses so certain and credible. For when we have the prophets and apostles agreeing with us, nay, as the ministers of our faith, and God as the author, and angels as approvers, there is no reason that the ungodly, all united, should move us from our position. By the commandment of the apostles he means the whole doctrine in which they had instructed the faithful. 
3. Knowing this first. The participle knowing may be applied to the Apostle, and in this way, "I labor to stir you up for this reason, because I know what and how great is your impending danger from scoffers." I however prefer this explanation, that the participle is used in place of a verb, as though he had said, "Know ye this especially." For it was necessary that this should have been foretold, because they might have been shaken, had impious men attacked them suddenly with scoffs of this kind. He therefore wished them to know this, and to feel assured on the subject, that they might be prepared to oppose such men.
But he calls the attention of the faithful again to the doctrine which he touched upon in the second chapter. For by the last days is commonly meant the kingdom of Christ, or the days of his kingdom, according to what Paul says, "Upon whom the ends of the world are come." (1 Corinthians 10:11.)  The meaning is, that the more God offers himself by the gospel to the world, and the more he invites men to his kingdom, the more audacious on the other hand will ungodly men vomit forth the poison of their impiety.
He calls those scoffers, according to what is usual in Scripture, who seek to appear witty by shewing contempt to God, and by a blasphemous presumption. It is, moreover, the very extremity of evil, when men allow themselves to treat the awful name of God with scoffs. Thus, the first Psalm speaks of the seat of scoffers. So David, in Psalm 119:51, complains that he was derided by the proud, because he attended to God's law. So Isaiah, in the 28th chapter, having referred to them, describes their supine security and insensibility. Let us therefore bear in mind, that there is nothing to be feared more than a contest with scoffers. On this subject we said something while explaining the third chapter of the Epistle to the Galatians. As, however, the Holy Scripture has foretold that they would come, and has also given us a shield by which we may defend ourselves, there is no excuse why we should not boldly resist them whatever devices they may employ.
4. Where is the promise. It was a dangerous scoff when they insinuated a doubt as to the last resurrection; for when that is taken away, there is no gospel any longer, the power of Christ is brought to nothing, the whole of religion is gone. Then Satan aims directly at the throat of the Church, when he destroys faith in the coming of Christ. For why did Christ die and rise again, except that he may some time gather to himself the redeemed from death, and give them eternal life? All religion is wholly subverted, except faith in the resurrection remains firm and immovable. Hence, on this point Satan assails us most fiercely.
But let us notice what the scoff was. They set the regular course of nature, such as it seems to have been from the beginning, in opposition to the promise of God, as though these things were contrary, or did not harmonize together. Though the faith of the fathers, they said, was the same, yet no change has taken place since their death, and it is known that many ages have passed away. Hence they concluded that what was said of the destruction of the world was a fable; because they conjectured, that as it had lasted so long, it would be perpetual.
 The Apostle evidently admits that they had a sincere or a pure mind, that is, freed from the pollutions referred to in the last chapter; but still they stood in need of being stirred up by admonitions: hence their minds were not, in a strict sense, perfect, though sincere. -- Ed.  The construction of the passage is as follows: -- "In both which I, by admonition, arouse your sincere mind to remember the words, aforetime spoken by the holy prophets, and the doctrine of us, the apostles of our Lord and Savior." The verb mnesthonai is connected with "arouse;" and it is in this tense used actively as well as passively. See Matthew 26:75, and Acts 10:31. There is in the noun entole, a metonymy, the commandment for what was commanded to be taught, the doctrine. It has this meaning, according to Schleusner, in John 12:50, and in this Epistle, chapter 2:21. -- Ed  It is literally, "the last of the days," according to the Hebrew form 'chryt hymym, "the extremity of the days," (Isaiah 2:2;) but the meaning is the same as "the last days," as used in Hebrews 1:2, and in other places, that is, the days of the gospel dispensation. -- Ed.
 The construction of the passage is as follows: -- "In both which I, by admonition, arouse your sincere mind to remember the words, aforetime spoken by the holy prophets, and the doctrine of us, the apostles of our Lord and Savior." The verb mnesthonai is connected with "arouse;" and it is in this tense used actively as well as passively. See Matthew 26:75, and Acts 10:31. There is in the noun entole, a metonymy, the commandment for what was commanded to be taught, the doctrine. It has this meaning, according to Schleusner, in John 12:50, and in this Epistle, chapter 2:21. -- Ed
 It is literally, "the last of the days," according to the Hebrew form 'chryt hymym, "the extremity of the days," (Isaiah 2:2;) but the meaning is the same as "the last days," as used in Hebrews 1:2, and in other places, that is, the days of the gospel dispensation. -- Ed.