Jesus Christ's fifth message to the churches of Revelation 2 and 3 was poignantly illustrated by first-century Sardis. This city had been one of the foremost cities of Asia Minor a few centuries earlier, but now it was in obvious decline. While the previously mentioned cities of the area were bustling with growth and activity (Pergamum as the capital city of Asia Minor, Ephesus as the largest city, Thyatira with its famous manufacturing center and Smyrna with its magnificent natural harbor and trade), Sardis was a relatively quiet city only able to reminisce upon past glory.
"Sardis was situated on the east bank of the Pactolus River about 80 kilometers (50 miles) east of Smyrna; it occupied a rocky spur of Mount Tmolus and a valley at the foot of this mountain. In ancient times Sardis was well fortified and easily defended. It became the capital of the ancient Lydian empire, then passed successively to the Persians, the Greeks, and the Romans during their respective dominance of the ancient world...
"The most impressive building of ancient Sardis must have been its magnificent Temple of Artemis, built in the fourth century B.C. The temple was 100 meters (327 feet) long and 50 meters (163 feet) wide and had 78 Ionic columns, each 17.7 meters (58 feet) high. Some of these columns remain standing until this day" (Nelson's Illustrated Bible Dictionary, 1986, article "Sardis").
Another source adds, "This important city was...located on important commercial routes running E and W through the rich kingdom of Lydia, of which it was the capital. It was also made wealthy by textile manufacturing and jewelry making. Here are said to have been minted the first coins under the opulent Croesus" (New Unger's Bible Dictionary, 1988, article "Sardis").
"It was moreover one of the oldest and most important cities of Asia Minor, and until 549 B.C., the capital of the kingdom of Lydia. It stood on the northern slope of Mt. Tmolus; its acropolis occupied one of the spurs of the mountain. At the base flowed the river Pactolus which served as a moat, rendering the city practically impregnable. Through the failure to watch, however, the acropolis had been successfully scaled in 549 B.C. by a Median soldier, and in 218 by a Cretan (compare Revelation 3:2-3 Revelation 3:2-3  Be watchful, and strengthen the things which remain, that are ready to die: for I have not found your works perfect before God.
 Remember therefore how you have received and heard, and hold fast, and repent. If therefore you shall not watch, I will come on you as a thief, and you shall not know what hour I will come on you.
American King James Version×)...
"The ancient city was noted for its fruits and wool, and for its temple of the goddess Cybele, whose worship resembled that of Diana of Ephesus. Its wealth was also partly due to the gold which was found in the sand of the river Pactolus, and it was here that gold and silver coins were first struck. During the Roman period its coins formed a beautiful series, and are found in abundance by the peasants who till the surrounding fields.
"The ruins of the buildings which stood at the base of the hill have now been nearly buried by the dirt washed down from above. The hill upon which the acropolis stood measures 950 ft. high: the triple walls still surround it. The more imposing of the ruins are on the lower slope of the hill, and among them the temple of Cybele is the most interesting, yet only two of its many stone columns are still standing" (International Standard Bible Encylopaedia, Electronic Database, 1996, article "Sardis").
"Only twice in the history of Sardis was its fortress ever captured, though attacks on it were frequent. When Cyrus attacked it in the sixth century B.C., a shrewd Persian soldier observed a Sardian descending the southern winding path to retrieve his fallen helmet. Unknown to the soldier, the Persians followed his path back up to the summit and captured the whole city, taking them quite by surprise. There was a similar occurrence when Antiochus attacked Sardis about two hundred years later...Sardis retained its wealth into the first two centuries of the Christian Era. But its political brilliance as the capital city of Asia for Persia lay in the past" (Expositor's Bible Commentary of the New Testament).
There is an ominous lesson to the history of Sardis: Even though it once had great prosperity, it now lies desolate. It did not endure. Its citizens lacked the foresight to look ahead and preserve their future. At the end of the first century, this city was a sad contrast between past splendor and present decay.
The history of Sardis was a perfect illustration of the timeless message Jesus delivered to His people: "Don't go to sleep. Remain spiritually alert!" Even though the Sardians had enjoyed great success, their failure to remain alert had twice led to military defeat—they were overtaken by surprise attacks. Noting the similarities between this city's history and the congregation's spiritual condition, Jesus said, "You are alive, but you are dead" (Revelation 3:1 Revelation 3:1And to the angel of the church in Sardis write; These things said he that has the seven Spirits of God, and the seven stars; I know your works, that you have a name that you live, and are dead.
American King James Version×).
Jesus then warned them and us today to "hold fast and repent" (verse 3) of spiritual drowsiness. And how did Jesus say this should be done? He twice referred to watching—"be watchful" (verse 2) and "if you will not watch, I will come upon you as a thief" (verse 3).
The Meaning of "Watch"
The Greek word gregoreo, translated "watchful" and "watch" in these two verses, "is used (a) of 'keeping awake,'… (b) of 'spiritual alertness'" (Vine's Expository Dictionary of Biblical Words, 1985, article "Watch (noun and verb), Watchers, Watchful, Watchings"). This word thus combines the sense of being physically awake with spiritual discernment. It is a spiritual condition of readiness and being alert. Those who do not maintain this approach will be surprised by Christ's return. Just as a thief is able to steal from unsuspecting victims, Christ's second coming will surprise those who are not spiritually alert (verse 3).
Earlier in His earthly ministry, Jesus addressed this concept via several parables. After listing some of the signs of His return (Matthew 24:3-31 Matthew 24:3-31  And as he sat on the mount of Olives, the disciples came to him privately, saying, Tell us, when shall these things be? and what shall be the sign of your coming, and of the end of the world?
 And Jesus answered and said to them, Take heed that no man deceive you.
 For many shall come in my name, saying, I am Christ; and shall deceive many.
 And you shall hear of wars and rumors of wars: see that you be not troubled: for all these things must come to pass, but the end is not yet.
 For nation shall rise against nation, and kingdom against kingdom: and there shall be famines, and pestilences, and earthquakes, in divers places.
 All these are the beginning of sorrows.
 Then shall they deliver you up to be afflicted, and shall kill you: and you shall be hated of all nations for my name's sake.
 And then shall many be offended, and shall betray one another, and shall hate one another.
 And many false prophets shall rise, and shall deceive many.
 And because iniquity shall abound, the love of many shall wax cold.
 But he that shall endure to the end, the same shall be saved.
 And this gospel of the kingdom shall be preached in all the world for a witness to all nations; and then shall the end come.
 When you therefore shall see the abomination of desolation, spoken of by Daniel the prophet, stand in the holy place, (whoever reads, let him understand:)
 Then let them which be in Judaea flee into the mountains:
 Let him which is on the housetop not come down to take any thing out of his house:
 Neither let him which is in the field return back to take his clothes.
 And woe to them that are with child, and to them that give suck in those days!
 But pray you that your flight be not in the winter, neither on the sabbath day:
 For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.
 And except those days should be shortened, there should no flesh be saved: but for the elect's sake those days shall be shortened.
 Then if any man shall say to you, See, here is Christ, or there; believe it not.
 For there shall arise false Christs, and false prophets, and shall show great signs and wonders; so that, if it were possible, they shall deceive the very elect.
 Behold, I have told you before.
 Why if they shall say to you, Behold, he is in the desert; go not forth: behold, he is in the secret chambers; believe it not.
 For as the lightning comes out of the east, and shines even to the west; so shall also the coming of the Son of man be.
 For wherever the carcass is, there will the eagles be gathered together.
 Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:
 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.
 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.
American King James Version×), He likened these to the signs of a fig tree identifying the season of the year. When leaves began to appear, everyone knew summer was near. His point in relation to His return was: "So you also, when you see all these things, know that it is near—at the doors!" (verse 33).
Jesus then explained that His return would surprise many people just as the Flood had done in Noah's day (verses 36-41). His advice? "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" (verses 42-44).
The parable about 10 virgins also illustrates this important principle (Matthew 25:1-13 Matthew 25:1-13  Then shall the kingdom of heaven be likened to ten virgins, which took their lamps, and went forth to meet the bridegroom.
 And five of them were wise, and five were foolish.
 They that were foolish took their lamps, and took no oil with them:
 But the wise took oil in their vessels with their lamps.
 While the bridegroom tarried, they all slumbered and slept.
 And at midnight there was a cry made, Behold, the bridegroom comes; go you out to meet him.
 Then all those virgins arose, and trimmed their lamps.
 And the foolish said to the wise, Give us of your oil; for our lamps are gone out.
 But the wise answered, saying, Not so; lest there be not enough for us and you: but go you rather to them that sell, and buy for yourselves.
 And while they went to buy, the bridegroom came; and they that were ready went in with him to the marriage: and the door was shut.
 Afterward came also the other virgins, saying, Lord, Lord, open to us.
 But he answered and said, Truly I say to you, I know you not.
 Watch therefore, for you know neither the day nor the hour wherein the Son of man comes.
American King James Version×). Five were wise and five were foolish. All went out to meet Christ, the bridegroom, but only five had the foresight to take sufficient oil for their lamps. Because Jesus was delayed, "they all slumbered and slept" (verse 5). When the announcement came of His coming, the foolish had to go buy oil for their lamps and only the wise who had made ample preparations were admitted to the wedding supper.
Jesus' moral to the story? "Watch therefore, for you know neither the day nor the hour in which the Son of Man is coming" (verse 13).
Like the parable of the 10 virgins, the message to Sardis shows the importance of spiritual preparedness. If we go to sleep spiritually, become lackadaisical or lose our zeal for God's way of life, we must repent and become spiritually alert once again.
Christ's instructions to Sardis emphasize this lesson. Some of the members in Sardis had become lethargic—lacking a spiritual focus—and Jesus warned them to "be watchful" so they would be prepared for His return (verse 2).
The Reward for Watching
After giving the instruction to be spiritually alert, Jesus said, "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, and I will not blot out his name from the Book of Life; but I will confess his name before My Father and before His angels" (Revelation 3:4-5 Revelation 3:4-5  You have a few names even in Sardis which have not defiled their garments; and they shall walk with me in white: for they are worthy.
 He that overcomes, the same shall be clothed in white raiment; and I will not blot out his name out of the book of life, but I will confess his name before my Father, and before his angels.
American King James Version×).
This passage also appears to reflect Christ's intimate knowledge of this first century congregation. Expositor's explains, "While the majority had departed from faithful obedience to Christ, a few at Sardis remained true. Here an allusion to the wool industry at Sardis intensifies the image of soiled and defiled garments. Those with soiled garments were removed from the public lists of citizens in Sardis. In the pagan religions it was forbidden to approach the gods in garments that were soiled or stained (Barclay, Seven Churches, p. 77). Soiling seems to be a symbol for mingling with pagan life and thus defiling the purity of one's relation to Christ."
Just as clean garments were required for those in Sardis to be included in their local census, clean garments (representing righteous actions, Revelation 19:8 Revelation 19:8And to her was granted that she should be arrayed in fine linen, clean and white: for the fine linen is the righteousness of saints.
American King James Version×) are required of all who will be included in "the Book of Life."
Paul also likened Christianity to clothing that must be put on when we commit ourselves to God's way of life. We must set our minds "on things above" and "put on the new man" with its accompanying actions (Colossians 3:2 Colossians 3:2 Set your affection on things above, not on things on the earth.
American King James Version×, 10). Continuing, he wrote, "Therefore, as the elect of God, holy and beloved, put on tender mercies, kindness, humility, meekness, longsuffering" (verse 12).
Jesus Christ's instructions to Sardis are universal instructions for God's people throughout the ages. As the message concludes, "'He who has an ear, let him hear what the Spirit says to the churches'" (Revelation 3:6 Revelation 3:6He that has an ear, let him hear what the Spirit said to the churches.
American King James Version×).
On the eve of Armageddon, "the battle of that great day of God Almighty," Jesus again cautions all, "Behold, I am coming as a thief. Blessed is he who watches, and keeps his garments..." (Revelation 16:14-16 Revelation 16:14-16  For they are the spirits of devils, working miracles, which go forth to the kings of the earth and of the whole world, to gather them to the battle of that great day of God Almighty.
 Behold, I come as a thief. Blessed is he that watches, and keeps his garments, lest he walk naked, and they see his shame.
 And he gathered them together into a place called in the Hebrew tongue Armageddon.
American King James Version×). UN