Revelation 3:16 So then because thou art lukewarm, and neither cold nor hot, I will spue thee out of my mouth.
What does this mean? 
Seems to me like God cares a lot about our attitudes, behavior, faith that results in our loving treatment of othes and deals with us accordingly. Drinks are best hold or cold, not lukewarm. Just as a lukewarm drink for us is no good so a heart that is lukewarm is no good to God. Weâll spue out the drink and heâll spue out us. I donât think this means he gives up on us, but that he deals with us through consequences, the first of which is spuing as out and telling us that we donât have fellowship with him. Itâs an eye opener and necessary for us to get the point.
Rev 3:16 is addressed to the CHURCH
When one feels sick about hypocrisy and lack of transformation and passion among professed christians that feeling is the same as Jesus feels about it. âLOOK OUT! Iâm Gonna SPEW!â
Do you ever get so fed up with Christians that it makes you gag? They sit in the pews week after week and they have some favorite rules they keep but their lives are not transformed. Behind closed doors, they indulge their flesh. They sigh and excuse themselves âIâm just a sinner and I canât help myself⌠At least Iâm not wicked like those _______ out there corrupting the society⌠â
Does it make you sick to your stomach and you just want to
SPEW,
HURL,
VOMIT?
Guess what?
You are in good company! 
Amen, Gem 
This has nothing to do with the unbeliever and ECT.
If it has anything to do with unbelievers at all, it would be that God would rather someone be cold for Him than lukewarm!âi.e. God can respect an honest unbeliever and work with him, and would rather have that than a lukewarm (and probably hypocritical) âChristianâ.
The cultural context however is that the city being discussed didnât have good sources of water nearby and so had to pipe it in (if not ship it in!) from elsewhere. By the time it arrived it was lukewarm and rather nauseating, and would also have to be settled to filter out the minerals (which was also a cooling process fortunately) or else boiled for recovery.
Cold water and hot water were useful to the city, but troublesome to come by. Lukewarm water was plentiful but nauseating. In local contexts the readers wouldnât have read the warning as meaning cold=unbeliever and hot=zealous believer, but cold and hot both being useful believers (maybe like cold water for refreshing a guest and hot water for cleaning a guest, in relation to local evangelism.)
That being said, it could also mean both things. To be zealous for Christ compared to being cold for Christ could be read as the heartâs attitude to Christ just as well as the different kinds of useful service for Christ.
Thanks guysâŚ
How would you know if you or another person were âlukewarmâ? The Hebrew letter describes the church there as âdull of hearingâ but still in Christ, no?
I think it has a lot to do with hunger. you have to be hungry for God in order to be fed of his truths.
Another way to look at it is, the person on fire for God is the one walking in truth.
the one who is cold against God is walking in misunderstanding and even desception.
God can work with both of those easily enough. But the guy who couldnât care less either way itâs in deception or truth either one.
Some foods are meant to be eaten hot, some are meant to be taken cold, it depends on what the food is. Perhaps the hot or cold in God could be under the same principle. Some people are so awesome to be around because they have a refreshing perspective and come as a cool breeze in our lives. Other times, we need to have the people who come in fire, in passion, in great expression . . .but the people who never seem to care about anything are shallow in most everything that they do, thereâs no depth in them.
But I do agree that I donât think this has to do with sinners versus saints . . .in fact, I think the same is true with about 99.9% of the rest of Scripture as well. Itâs more about those in religion versus those in faith.
Regardless of which meaning (or both) is true of âlukewarmâ, I would expect it to mean something like the baby goats from GosMatt 25. Time servers who are in it for a gnostic fire insurance, or for merely technical knowledge, or for the social advantages, who donât care about fulfilling fair-togetherness between persons and helping those in need, working with Christ in His work and yoke, but who rather bury their talent in the ground⌠those seem like a standard and accepted category of lukewarm Christians to me.
Christ had some warnings for the zealous Christians at Ephesus, too, of course. Lots of compliments for them, too, unlike at Laodicia, but still they had abandoned their first (or chief or foundational) love in doing those good worksâeven bearing up under torments, and being concerned enough with truth to even test apostles! All commendable things, but without agapeâŚ
That âisâ the one thing that stands out to me in the seven letters. To each one Jesus stated "I see your works, I see your works, I see your works . . âŚ
Itâs not that having works is a bad thing, itâs that most churches have spent so much time and energy focusing on personal works that theyâve shifted the true emphasis âfromâ grace. I think that may be what âfallen from graceâ is all about. Itâs not weâre so bad that grace no longer can cover us, itâs that weâre so busy paying attention to our outward actions and appearance that weâve stopped reaping the benefits of the infinite grace bestowed upon us in the first place. It should never be about how disciplined I am as a follower of Christ. It should be more about the greatness of his grace manifesting in my life âin spiteâ of my âselfâ.
Makes sense, thanks guys. I hate lukewarm water, so i guess its similar to that. 
I think most ECT like to think of it as literal in some wayâŚlike they do everything else. 