1 Peter 4:7

We have here an awful position or doctrine, and an inference drawn from it. The position is that the end of all things is at hand. The miserable destruction of the Jewish church and nation foretold by our Saviour is now very near; consequently, the time of their persecution and your sufferings is but very short. Your own life and that of your enemies will soon come to their utmost period. Nay, the world itself will not continue very long. The conflagration will put an end to it; and all things must be swallowed up in an endless eternity. The inference from this comprises a series of exhortations. 1. To sobriety and watchfulness: "Be you therefore sober, Pe1 4:7. Let the frame and temper of your minds be grave, stayed, and solid; and observe strict temperance and sobriety in the use of all worldly enjoyments. Do not suffer yourselves to be caught with your former sins and temptations, Pe1 4:3. An watch unto prayer. Take care that you be continually in a calm sober disposition, fit for prayer; and that you be frequent in prayers, lest this end come upon you unawares," Luk 21:34; Mat 26:40, Mat 26:41. Learn, (1.) The consideration of our approaching end is a powerful argument to make us sober in all worldly matters, and earnest in religious affairs. (2.) Those who would pray to purpose must watch unto prayer.

— Matthew Henry's Concise Commentary (public domain)

Resuming the idea in Pe1 4:5. the end of all things--and therefore also of the wantonness (Pe1 4:3-4) of the wicked, and of the sufferings of the righteous [BENGEL]. The nearness meant is not that of mere "time," but that before the Lord; as he explains to guard against misapprehension, and defends God from the charge of procrastination: We live in the last dispensation, not like the Jews under the Old Testament. The Lord will come as a thief; He is "ready" (Pe1 4:5) to judge the world at any moment; it is only God's long-suffering and His will that the Gospel should be preached as a witness to all nations, that induces Him to lengthen out the time which is with Him still as nothing. sober--"self-restrained." The opposite duties to the sins in Pe1 4:3 are here inculcated. Thus "sober" is the opposite of "lasciviousness" (Pe1 4:3). watch--Greek, "be soberly vigilant"; not intoxicated with worldly cares and pleasures. Temperance promotes wakefulness or watchfulness, and both promote prayer. Drink makes drowsy, and drowsiness prevents prayer. prayer--Greek, "prayers"; the end for which we should exercise vigilance.

— Jamieson-Fausset-Brown Commentary (public domain)