The {l} last enemy that shall be destroyed is death.

(l) The conclusion of the argument, which is taken from the whole to the part: for if all his enemies will be put under his feet, then it will necessarily be that death also will be subdued under him.

People's New Testament

15:26 The last enemy... is death. See Re 20:12-14. The order there of closing events is the resurrection, the judgment, and the casting of Death and Hades (hades--the grave) into the lake of fire.

Wesley's Notes

15:26 The last enemy that is destroyed is death - Namely, after Satan, Heb 2:14, and sin, 1Cor 15:56, are destroyed. In the same order they prevailed. Satan brought in sin, and sin brought forth death. And Christ, when he of old engaged with these enemies, first conquered Satan, then sin, in his death; and, lastly, death, in his resurrection. In the same order he delivers all the faithful from them, yea, and destroys these enemies themselves. Death he so destroys that it shall be no more; sin and Satan, so that they shall no more hurt his people.

Jamieson-Fausset-Brown Bible Commentary

26. shall be-Greek, "is done away with" (Re 20:14; compare Re 1:18). It is to believers especially this applies (1Co 15:55-57); even in the case of unbelievers, death is done away with by the general resurrection. Satan brought in sin, and sin brought in death! So they shall be destroyed (rendered utterly powerless) in the same order (1Co 15:56; Heb 2:14; Re 19:20; 20:10, 14).

Matthew Henry's Concise Commentary

15:20-34 All that are by faith united to Christ, are by his resurrection assured of their own. As through the sin of the first Adam, all men became mortal, because all had from him the same sinful nature, so, through the resurrection of Christ, shall all who are made to partake of the Spirit, and the spiritual nature, revive, and live for ever. There will be an order in the resurrection. Christ himself has been the first-fruits; at his coming, his redeemed people will be raised before others; at the last the wicked will rise also. Then will be the end of this present state of things. Would we triumph in that solemn and important season, we must now submit to his rule, accept his salvation, and live to his glory. Then shall we rejoice in the completion of his undertaking, that God may receive the whole glory of our salvation, that we may for ever serve him, and enjoy his favour. What shall those do, who are baptized for the dead, if the dead rise not at all? Perhaps baptism is used here in a figure, for afflictions, sufferings, and martyrdom, as Mt 20:22,23. What is, or will become of those who have suffered many and great injuries, and have even lost their lives, for this doctrine of the resurrection, if the dead rise not at all? Whatever the meaning may be, doubtless the apostle's argument was understood by the Corinthians. And it is as plain to us that Christianity would be a foolish profession, if it proposed advantage to themselves by their faithfulness to God; and to have our fruit to holiness, that our end may be everlasting life. But we must not live like beasts, as we do not die like them. It must be ignorance of God that leads any to disbelieve the resurrection and future life. Those who own a God and a providence, and observe how unequal things are in the present life, how frequently the best men fare worst, cannot doubt as to an after-state, where every thing will be set to rights. Let us not be joined with ungodly men; but warn all around us, especially children and young persons, to shun them as a pestilence. Let us awake to righteousness, and not sin.