Lukewarm Christians are people that put the their needs in this world above a relationship with Christ. In context, here is the scripture you reference:
Rev 3:16 - 'So because you are lukewarm, and neither hot nor cold, I will spit you out of My mouth.
Rev 3:17 - 'Because you say, "I am rich, and have become wealthy, and have need of nothing," and you do not know that you are wretched and miserable and poor and blind and naked,
Rev 3:18 - I advise you to buy from Me gold refined by fire so that you may become rich, and white garments so that you may clothe yourself, and that the shame of your nakedness will not be revealed; and eye salve to anoint your eyes so that you may see.
Rev 3:19 - 'Those whom I love, I reprove and discipline; therefore be zealous and repent.
Rev 3:20 - 'Behold, I stand at the door and knock; if anyone hears My voice and opens the door, I will come in to him and will dine with him, and he with Me.
Rev 3:21 - 'He who overcomes, I will grant to him to sit down with Me on My throne, as I also overcame and sat down with My Father on His throne.
Rev 3:22 - 'He who has an ear, let him hear what the Spirit says to the churches.'"[NASB]
This is the Believer's Bible Commentary view on the passage:
3:15-17 - The church at Laodicea was neither cold nor hot. It was sickeningly lukewarm. The Lord would have preferred it to have been extreme in its indifference or its zeal. But no—it was lukewarm enough to deceive people into thinking that it was a church of God, and so disgustingly lukewarm about divine things as to nauseate the Most High. Furthermore, the church was characterized by pride, ignorance, self-sufficiency, and complacency.
3:18 - The people were counseled to buy from the Lord gold refined in the fire. This may mean divine righteousness, which is bought without money or price (Isaiah 55:1) but received as a gift through faith in the Lord Jesus. Or it may mean genuine faith, which when tested in the fire, results in praise, honor, and glory at the revelation of Jesus Christ (1 Peter 1:7).
Also the people were counseled to buy white garments, that is, practical righteousness in everyday life. And they should anoint their eyes with eye salve, that is, gain true spiritual vision through the enlightenment of the Holy Spirit. This counsel was especially appropriate, since Laodicea was known as a center for banking, textiles, and medicines—especially eye salve.
3:19 - The Lord's love for the church is seen in the fact that He rebukes and chastens it. If He did not care, He would not bother. With lingering tenderness, He calls on this nominal church to be zealous and repent.
3:20 - In the closing verses, we have what Scofield calls “the place and attitude of Christ at the end of the church age.” He is outside the professing church, politely knocking and inviting individuals (no longer the mass of the people) to leave the apostate church in order to have fellowship with Him.
Trench comments:
Every man is lord of the house of his own heart; it is his fortress; he must open the gates of it. He has the mournful prerogative and privilege of refusing to open. But if he refuses, he is blindly at strife with his own blessedness, a miserable conqueror.
3:21 - The overcomer is promised that he will share the glory of Christ's throne and reign with Him over the millennial earth. Those who follow Him in humility, rejection, and suffering will also follow Him in glory.
3:22 - Then for the last time, the hearer is solemnly advised to listen to the voice of the Spirit.
Whatever interpretation we take of the book of Revelation, it is undeniable that the church of Laodicea presents a vivid picture of the age in which we live. Luxury-living abounds on every hand while souls are dying for want of the gospel. Christians are wearing crowns instead of bearing a cross. We become more emotionally stirred over sports, politics, or television than we do over Christ. There is little sense of spiritual need, little longing for true revival. We give the best of our lives to the business world, then turn over the remnants of a wasted career to the Savior. We cater to our bodies which in a few short years will return to dust. We accumulate instead of forsake, lay up treasures on earth instead of in heaven. The general attitude is, “Nothing too good for the people of God. If I don't pamper myself, who will? Let's get ahead in the world and give our spare evenings to the Lord.” This is our condition on the eve of Christ's Return.
I believe the passage, in context, makes it clear that if we put the things of this world ahead of the Lord and do not repent, the Lord will not have anything to do with us in the world to come. At least, that's my opinion.
