1 Peter 3:18

For Christ also hath once suffered for sins
Not his own, for he committed none, but for the sins of his people; in order to obtain the remission of them, to make reconciliation for them, and to take and put them away, and finish and make an end of them; which sufferings of his, on account of them, were many and great: he suffered much by bearing the griefs, and carrying the sorrows of his people, whereby he became a man of sorrows, and acquainted with griefs, from his cradle to his cross; and from the temptations of Satan, being in all points tempted, as his members are, though without sin; and from the contradiction of sinners against him, in his name, credit, and character, abusing him as the worst of men; and he suffered in his soul, from the wrath of God, and curses of the law, which lay upon him; and in his body, by many buffetings, scourges, wounds, and death itself, even the death of the cross; and which being the finishing part of his sufferings, is chiefly here meant. The Alexandrian copy reads, "died for you"; and the Vulgate Latin, Syriac, and Ethiopic versions read, "died for our sins"; and this he did once, and but once; he died once, and will die no more; he was offered up once, and will be offered up no more; there is no more offering, or sacrifice for sin; the reason is, because his one offering is sufficient to take away sin, which the legal sacrifices were not, and therefore were often offered; and the reason why this his one offering, or once suffering and dying, is sufficient, is, because of his divine nature, or eternal Spirit, by which he offered himself, and gave infinite virtue to his sacrifice and satisfaction: now, this is an argument for suffering patiently; since Christ, the head, has also suffered, and therefore, why not the members? and since he has suffered for their sins, therefore they should not grudge to suffer for his sake; and seeing also their sufferings are but once, in this life only, and as it were but for a moment, and not to be compared with his sufferings for them; and especially when it is considered what follows:

the just for the unjust;
Christ, the holy and just one, who is holy in his nature, and righteous in his life and actions, which were entirely conformable to the righteous law of God, and upright and faithful in the discharge of his office, and therefore called God's righteous servant; he suffered, and that not only by unjust men, by the Jews, by Pilate, and the Roman soldiers, but for and in the room and stead of unjust men, sinners, and ungodly, who were destitute of righteousness, and full of all unrighteousness; and since he did, it need not be thought hard, or strange, that sinful men should suffer at the hands of others; and still it should be borne with the greater patience, since Christ not only suffered for them, but since an end is answered by it, as is here suggested:

that he might bring us to God;
nigh to God, who, with respect to communion, were afar off from him; and in peace and reconciliation with him, who were enemies to him by wicked works; and that they might have freedom of access, with boldness, unto God, through his precious blood, and the vail of his flesh; and that he might offer them unto God, as the Vulgate Latin and Syriac versions render it; as a sacrifice acceptable unto God, presenting them to him unblamable and unreproveable in his sight; that he might bring them into his grace and presence here, and, as the great Captain of their salvation, bring them to him in glory hereafter:

being put to death in the flesh;
in the human nature: flesh includes the whole of human nature, both body and soul; for though the body only dies, yet death is the dissolution of the union between them both; and such was Christ's death; for though the union between the two natures continued, yet his body and soul were disunited; his body was left on the cross, and his soul, or Spirit, was commended to God, when his life was taken from the earth, and he was put to death in a violent manner by men:

but quickened by the Spirit;
raised from the dead by his divine nature, the Spirit of holiness, the eternal Spirit, by which he offered himself, and by virtue of which, as he had power to lay down his life, so he had power to take it up again; when he was also justified in the Spirit, and all the elect in him. Now, as the enemies of Christ could do no more than put him to death in the flesh, so the enemies of his people can do no more than kill the body, and cannot reach the soul; and as Christ is quickened and raised from the dead, so all his elect are quickened together, and raised with him, representatively, and shall, by virtue of his resurrection, be raised personally, and live also; which is no inconsiderable argument to suffer afflictions patiently, and which is the design of this instance and example of the sufferings, death, and resurrection of Christ.