1:1-4 Christians are called out of the world, from the evil spirit and temper of it; called above the world, to higher and better things, to heaven, things unseen and eternal; called from sin to Christ, from vanity to seriousness, from uncleanness to holiness; and this according to the Divine purpose and grace. If sanctified and glorified, all the honour and glory must be ascribed to God, and to him alone. As it is God who begins the work of grace in the souls of men, so it is he who carries it on, and perfects it. Let us not trust in ourselves, nor in our stock of grace already received, but in him, and in him alone. The mercy of God is the spring and fountain of all the good we have or hope for; mercy, not only to the miserable, but to the guilty. Next to mercy is peace, which we have from the sense of having obtained mercy. From peace springs love; Christ's love to us, our love to him, and our brotherly love to one another. The apostle prays, not that Christians may be content with a little; but that their souls and societies may be full of these things. None are shut out from gospel offers and invitations, but those who obstinately and wickedly shut themselves out. But the application is to all believers, and only to such. It is to the weak as well as to the strong. Those who have received the doctrine of this common salvation, must contend for it, earnestly, not furiously. Lying for the truth is bad; scolding for it is not better. Those who have received the truth must contend for it, as the apostles did; by suffering with patience and courage for it, not by making others suffer if they will not embrace every notion we call faith, or important. We ought to contend earnestly for the faith, in opposition to those who would corrupt or deprave it; who creep in unawares; who glide in like serpents. And those are the worst of the ungodly, who take encouragement to sin boldly, because the grace of God has abounded, and still abounds so wonderfully, and who are hardened by the extent and fulness of gospel grace, the design of which is to deliver men from sin, and bring them unto God.
3. Design of the Epistle (compare Jude 20, 21).
all diligence—(2Pe 1:5). As the minister is to give all diligence to admonish, so the people should, in accordance with his admonition, give all diligence to have all Christian graces, and to make their calling sure.
the common salvation—wrought by Christ. Compare Note, see on 2Pe 1:1, "obtained LIKE precious faith," This community of faith, and of the object of faith, salvation, forms the ground of mutual exhortation by appeals to common hopes and fears.
it was needful for me—rather, "I felt it necessary to write (now at once; so the Greek aorist means; the present infinitive 'to write,' which precedes, expresses merely the general fact of writing) exhorting you." The reason why he felt it necessary "to write with exhortation," he states, Jude 4, "For there are certain men crept in," &c. Having intended to write generally of "the common salvation," he found it necessary from the existing evils in the Church, to write specially that they should contend for the faith against those evils.
earnestly contend—Compare Php 1:27, "striving together for the faith of the Gospel."
once, &c.—Greek, "once for all delivered." No other faith or revelation is to supersede it. A strong argument for resisting heretical innovators (Jude 4). Believers, like Nehemiah's workmen (Ne 4:17), with one hand "build themselves up in their most holy faith"; with the other they" contend earnestly for the faith" against its foes.
the saints—all Christians, holy (that is, consecrated to God) by their calling, and in God's design.