There are two main interpretations regarding the interjection of these words of Christ at this point.
One interpretation understands the words as spoken to those believers who remain on earth during this time of awful turmoil and destruction. He is telling them to watch, remain faithful, and be ready for His Second Coming. Yet there seem to be some problems with such a premise. (1) The timing of the events attending the Tribulation, and especially the latter half, is not subject to uncertainty. We have seen numerous time-indicators in the text concerning a precise number of days following the abomination of desolation until the endthe Second Coming of Christ (Dan. Dan. 7:25; Dan. 9:27; Dan. 12:7; Rev. Rev. 11:2-3+; Rev. 12:6+, Rev. 12:14+; Rev. 13:5+). (2) It seems very unlikely that believers that remain during this timehaving survived the most politically and physically dangerous period of historyare at all likely to be found napping! They are risking everything to hold true to their faith in Christ and the conditions are such that they can only be constantly longing for His arrival. These reasons argue against the notion that Christ is speaking here of His Second Coming in judgment.
Another interpretation understands the words as an interjection for the readers of the vision which John was to write in a book and send it to the seven churches (Rev. Rev. 1:11+). The vision is given both for the seven churches and for the saints of all ages to follow, as is seen from the repeated phrase: He who has an ear, let him hear what the Spirit says to the churches (Rev. Rev. 2:7+, Rev. 2:11+, Rev. 2:17+, Rev. 2:29+; Rev. 3:6+, Rev. 3:13+, Rev. 3:22+). It is to these saints, upon which The Day of the Lord may come, that Jesus repeats His warning to watch (Rev. Rev. 3:3+). It is not necessary to relate this warning only to the end time as in the context, since the appeal for steadfast loyalty of Christians is relevant at any time.1 During the time between His ascension and His return for the Church, a long age rolls on. His departure is far behind while His return in the Rapture remains in the unforeseen future. This is the sleepy time when the status quo of the world distracts the saints and all things continue as they were from the beginning of creation (2Pe. 2Pe. 3:4).
Seiss suggests a third alternative: the words are in fact for the believers of this time of the end, but do not denote His Second Coming in judgmentan event whose timing is not subject to uncertainty once the Tribulation begins:
Somewhere about this time, then, Christ comes for this last band of children of the resurrection, whether dead or yet living. Of course, it is a coming of the same kind and character as his coming for those saints who were taken earlier; for it is the completion of that one coming for his people which is everywhere set forth. Here also, as in all other cases, nothing but a state of watchful readiness when the call comes can secure a share in the blessing.2In Seiss scenario, Christ comes for believers at a point in time prior to His actually setting foot on the earth in final judgment. He seems to suggest that a mini-rapture of sorts takes place at an unknown time prior to Christs physical coming. Perhaps this is to be connected with His promises to gather the elect by angels? One obstacle to this view is that the passages which stipulate the gathering of the elect follow immediately upon the global sign of the Son of Mans return (Mtt. Mat. 24:30-31; Mark Mark 13:26-27).
If the warning is an encouragement to the persecuted remnant under the beast, Christs promised coming is the one in Rev. Rev. 19:11-16+, which by the time of the sixth bowl follows almost immediately (Alford). If the warning is to people in the churches, it returns to the theme of chapters Rev. 2:1+-Rev. 3:1+, the imminence of the hour of trial as an incentive for the books recipients to make their calling and election sure so they can escape this coming dreaded period. The close similarity to Rev. Rev. 3:3+, Rev. 3:18+ and the parenthetical nature of the announcement favor the latter alternative. . . . The other possibility of this being an encouragement to the faithful to persevere could serve no useful purpose at this point. . . . Therefore this announcement is a repetition of excerpts from the two earlier messages to Sardis and Laodicea: it is a call to genuineness of faith.3as a thief
He only comes as a thief upon those who are not watching. Jesus told the church at Sardis, Be watchful, . . . if you will not watch, I will come upon you as a thief, and you will not know what hour I will come upon you (Rev. Rev. 3:3+). See commentary on Revelation 3:3.
Those who are in Christ are to be constantly on the lookout for His arrival, not that of Antichrist:
Watch therefore, for you do not know what hour your Lord is coming. But know this, that if the master of the house had known what hour the thief would come, he would have watched and not allowed his house to be broken into. Therefore, you also be ready, for the Son of Man is coming at an hour you do not expect. (Mtt. Mat. 24:42-44)
Take heed, watch and pray; for you do not know when the time is. It is like a man going to a far country, who left his house and gave authority to his servants, and to each his work, and commanded the doorkeeper to watch. Watch therefore, for you do not know when the master of the house is coming-in the evening, at midnight, at the crowing of the rooster, or in the morning- lest, coming suddenly, he find you sleeping. And what I say to you, I say to all: Watch! (Mark Mark 13:33-37)
Let your waist be girded and your lamps burning; and you yourselves be like men who wait for their master, when he will return from the wedding, that when he comes and knocks they may open to him immediately. Blessed are those servants whom the master, when he comes, will find watching. Assuredly, I say to you that he will gird himself and have them sit down to eat, and will come and serve them. And if he should come in the second watch, or come in the third watch, and find them so, blessed are those servants. But know this, that if the master of the house had known what hour the thief would come, he would have watched and not allowed his house to be broken into. Therefore you also be ready, for the Son of Man is coming at an hour you do not expect. (Luke Luke 12:35-40)Jesus indicated that a day was coming which would arrive unexpectedly as a snare to the earth dwellers, but by vigilance and prayer, the watchful believer could escape the things that were coming to pass:
But take heed to yourselves, lest your hearts be weighed down with carousing, drunkenness, and cares of this life, and that Day come on you unexpectedly. For it will come as a snare on all those who dwell on the face of the whole earth. Watch therefore, and pray always that you may be counted worthy to escape all these things that will come to pass, and to stand before the Son of Man. (Luke Luke 21:34-36)The day which He spoke of was The Day of the Lord which professing but unbelieving Christians, who miss the Rapture, will endure along with those dwelling upon the earth. For them, the beginning of the end comes as a surprise since they are not expecting it. It arrives, as a thief:
But concerning the times and the seasons, brethren, you have no need that I should write to you. For you yourselves know perfectly that the day of the Lord so comes as a thief in the night. For when they say, Peace and safety! then sudden destruction comes upon them, as labor pains upon a pregnant woman. And they shall not escape. But you, brethren, are not in darkness, so that this Day should overtake you as a thief. You are all sons of light and sons of the day. We are not of the night nor of darkness. Therefore let us not sleep, as others do, but let us watch and be sober. For those who sleep, sleep at night, and those who get drunk are drunk at night. But let us who are of the day be sober, putting on the breastplate of faith and love, and as a helmet the hope of salvation. For God did not appoint us to wrath, but to obtain salvation through our Lord Jesus Christ. (1Th. 1Th. 5:1-9)Jesus comes for those who are watching in the Rapture of the Church prior to this time (Luke Luke 21:34-36; John John 14:1-3). He comes as a thief in the night in the judgments which usher in The Day of the Lord, culminating with His personal arrival in judgment at the Second Coming to conclude the Campaign of Armageddon. See When Does the Day of the Lord Dawn?
blessed is he who watches
He who watches is ὁ γρηγορῶν [ho grēgorōn] , present tense participle, the one presently, continually watching.4 See commentary on Revelation 1:3. He is blessed because his nakedness is not seen. In his watchfulness, he evidences true faith.5
and keeps his garments
Keeping ones garments refers to the avoidance of sinful behavior and the continuance in the faith with confession in the event of sin (1Jn. 1Jn. 1:9). Christ told the church at Sardis, You have a few names even in Sardis who have not defiled their garments; and they shall walk with me in white, for they are worthy. He who overcomes shall be clothed in white garments (Rev. Rev. 3:4-5+). See commentary on Revelation 3:4.
lest he walk naked and they see his shame
Shame is ἀσχημοσύνην [aschēmosynēn] : Rev. 16:15+ for spiritual unpreparedness.6 Christ told the lukewarm church at Laodicea to buy from me gold refined in the fire, that you may be rich; and white garments, that you may be clothed, that the shame of your nakedness may not be revealed (Rev. Rev. 3:18+). This speaks of the internal reality of a persons walk being exposed for all to see (Isa. Isa. 47:1-3; Nah. Nah. 3:5). See commentary on Revelation 3:18.
Those who fail to watch were never true believers (Mtt. Mat. 24:42, Mat. 24:51). They are ones who will not be counted worthy to escape all these things that will come to pass (Luke Luke 21:36), they will not participate in the Rapture . Like Jezebel in the church at Thyatira who is a type of apostate believers of the end (Rev. Rev. 2:22+), they will find themselves in the Great Tribulation. Having proclaimed faith in Christ prior to the Rapture yet remaining on earth, their hypocrisy will be revealed for they will not be among those who are taken to the Fathers house (Rev. Rev. 14:1-3+).
Either this warning is meant parenthetically for readers prior to the time of the bowl judgments (the Church, to be taken at the Rapture before the wrath begins) or, if meant for believers on the earth at this time of the end, it may speak of the gathering of the elect shortly before the Second Comingalthough clear indications of a separate coming for the Tribulation saints ahead of His physical Second Coming are difficult to establish.7
See commentary on Revelation 16:15.
2 J. A. Seiss, The Apocalypse: Lectures on the Book of Revelation (Grand Rapids, MI: Zondervan Publishing House, 1966), 379.
4 The Gregorian chant is named after St. Gregory, the watching one.
5 Concerning the need for watchfulness: Mtt. Mat. 24:42; Mat. 25:13; Mark Mark 13:33, Mark 13:35, Mark 13:37; Luke Luke 12:36-40; Luke 21:36; 1Cor. 1Cor. 1:7; 1Cor. 16:13; Php. Php. 3:20; 1Th. 1Th. 1:10; 1Th. 5:6; 2Ti. 2Ti. 4:8; Tit. Tit. 2:13; Heb. Heb. 9:28; 2Pe. 2Pe. 3:12; Rev. Rev. 3:2-3+; Rev. Rev. 16:15+.