1. Although hypocrites and other unregenerate men may vainly deceive themselves with false hopes and carnal presumptions of being in the favor of God, and estate of salvation (Job 8:13–14; Micah 3:11; Deut. 29:19; John 8:41) (which hope of theirs shall perish) (Matt. 7:22–23): yet such as truly believe in the Lord Jesus, and love Him in sincerity, endeavouring to walk in all good conscience before Him, may, in this life, be certainly assured that they are in the state of grace (1 John 2:3; 3:14, 18, 19, 21, 24; 5:13), and may rejoice in the hope of the glory of God, which hope shall never make them ashamed (Rom. 5:2, 5).
The doctrine of perseverance is not one that may legitimately be used to comfort the unsaved. A debate over whether diamonds can be lost is no debate at all for a man who has no diamonds, only a clenched fist. Vain hypocrites and unregenerate professors have nothing but a false hope. They think they are in the favor of God, and they believe they have entered into the state of salvation. All their hopes shall die along with them.
But those who genuinely believe in Christ, and truly love Him, and who walk before Him with a clean conscience, may comfort themselves with an assurance that God will receive them at the last. This is a basis for strong joy, and such men will never be ashamed. This is not a weak hope, but rather a settled assurance.
2. This certainty is not a bare conjectural and probable persuasion grounded upon a fallible hope (Heb. 6:11, 19); but an infallible assurance of faith founded upon the divine truth of the promises of salvation (Heb. 6:17–18), the inward evidence of those graces unto which these promises are made (2 Pet. 1:4–5, 10–11; 1 John 2:3; 3:14; 2 Cor. 1:12), the testimony of the Spirit of adoption witnessing with our spirits that we are the children of God (Rom. 8:15–16), which Spirit is the earnest of our inheritance, whereby we are sealed to the day of redemption (Eph. 1:13–14; 4:30; 2 Cor. 1:21–22).
This is not a hope generated by men on the basis of a line of reasoning they have undertaken on their own authority. Rather, the assurance of the faithful is a work of grace. As such it is infallible. The hope is as secure as the promise upon which it is based. In addition, because the promises were not made to all and every, the hope is based upon an inward realization of the graces to which God spoke His promise—the fundamental grace being faith. Further, the Holy Spirit is a Spirit of adoption, and His work includes that of witnessing to our Spirit that we are in fact the children of God. As the earnest of our inheritance, this means that if a true child of God were to be lost and go to hell, then the Spirit would be forfeited as an earnest payment, and would accompany him there. Since this is clearly absurd, we know that someone who has this internal sealing of the Spirit cannot be lost.
3. This infallible assurance does not so belong to the essence of faith, but that a true believer may wait long, and conflict with many difficulties, before he be partaker of it (1 John 5:13; Isa. 1:10; Mark 9:24; Ps. 88; 77:1–12): yet, being enabled by the Spirit to know the things which are freely given him of God, he may, without extraordinary revelation, in the right use of ordinary means, attain thereunto (1 Cor. 2:12; 1 John 4:13; Heb. 6:11–12; Eph. 3:17–19). And therefore it is the duty of every one to give all diligence to make his calling and election sure (2 Pet. 1:10), that thereby his heart may be enlarged in peace and joy in the Holy Ghost, in love and thankfulness to God, and in strength and cheerfulness in the duties of obedience (Rom. 5:1–2, 5; 14:17; 15:13; Eph. 1:3–4; Ps. 4:6–7; Ps. 119:32), the proper fruits of this assurance; so far is it from inclining men to looseness (1 John 2:1–2; Rom. 6:1–2; Tit. 2:11–12, 14; 2 Cor. 7:1; Rom. 8:1, 12; 1 John 3:2–3; Ps. 130:4; 1 John 1:6–7).
This assurance is normative, but is not part of the essence of saving faith. This means that a man who doubts his salvation may not use those doubts as prima facie evidence that he is in fact unsaved. A genuine believer may go through many trials of assurance before he enjoys the grace of this assurance. Coming to this assurance does not require an extraordinary revelation from the Spirit of God; he should receive this assurance through ordinary means. Those ordinary means would be ordinary means of grace. Assurance of salvation, making one's calling and election sure, is a Christian duty. The result of this would be a heart enlarged in peace and joy given by the Holy Spirit, as well as love and thankfulness to God. Obedience would cease to be a chore, and become rather something conducted in strength and cheerfulness. All these things are a consequence of assurance, and it is very important to note that a biblical assurance is never an encouragement to looseness or laxity of life.
4. True believers may have the assurance of their salvation divers ways shaken, diminished, and intermitted; as, by negligence in preserving of it, by falling into some special sin which woundeth the conscience and grieveth the Spirit; by some sudden or vehement temptation, by God’s withdrawing the light of His countenance, and suffering even such as fear Him to walk in darkness and to have no light (Song 5:2–3, 6; Ps. 51:8, 12, 14; Eph. 4:30–31; Ps. 77:1–10; Matt. 26:69–72; Ps. 31:22; Ps. 88; Isa. 1:10): yet are they never utterly destitute of that seed of God, and life of faith, that love of Christ and the brethren, that sincerity of heart, and conscience of duty, out of which, by the operation of the Spirit, this assurance may, in due time, be revived (1 John 3:9; Luke 22:32; Job 13:15; Ps. 73:15; 51:8, 12; Isa. 1:10); and by the which, in the mean time, they are supported from utter despair (Micah 7:7–9; Jer. 32:40; Isa. 54:7–10; Ps. 22:1; Ps. 88.1).
The elect may lose their assurance in varying degrees. Their assurance may be rattled, lessened, or interrupted. This might come about because they took it for granted and did not preserve it—because they had assurance, they did not think that maintaining it was a duty. They may also lose assurance because of some notable sin which gives ground for self-accusation. With the Spirit grieved, the answers to the accusation are not forthcoming. They may lose assurance because of a vehement assault on their assurance. In other words, loss of assurance may not be the result of another sin; the temptation may be to lose assurance. The problem may occur because God withdraws from the believer to test and prove him, seeing if he doubts in the dark what he knew in the light.
Still, despite such losses, the genuine believer is never utterly destitute of the seed of God along with a remnant of saving faith. These things are not so declined as to make it impossible for a true Christian life to be revived—which means their love for Christ and Christians, sincerity of heart, and sense of duty may be restored. And when they are restored by the Spirit, their assurance will also be restored. And between the loss of assurance and the restoration, the Holy Spirit takes care to see that the believer is not crushed under the weight of complete despair.