Regarding the OP/thread topic, a few things to consider (IMO):
1) in the churchES, there exists both believers [saints] and those who are not [genuine saints]; whereas "the Church which is His body" consists ONLY of believers/saints [of 'this present age'... from the first century, up to our Rapture]
2) both "hot" and "cold" seem to be positives, from God's perspective (for it says, "I would thou wert hot or cold")
3) it is my understanding that "hot" and "cold" were waters originating from a particular source, whereas "lukewarm" was that which was not connected with such a source (sort of like a stagnant mudpuddle versus a river/stream [or aqueduct] or hot-springs kind of thing); thus, God "spews out of His mouth" the "lukewarm" who are not connected with the source: that is, He is looking to taste "Christ" in them, and lacking that, spews them out. So I tend to believe the "lukewarm" are those [in the churchES; i.e. in Christendom] who come in His name, but who are not vitally connected with/to The Source (Jesus Christ) [even Matt7 says some will say, "haven't WE DONE... many wonderful works" IN THY NAME, and He says unto them "I never knew you"]… IOW, I do not see the Rev3 passage as a "lose your salvation" context
[note: I tend to believe the "lukewarm," here, then are spewed into the tribulation period and there counseled to "buy of Me gold tried in the fire" 3:18, where also it says, "...that the shame of thy nakedness do not appear," which is very close to what is also stated in Revelation 16:15-16 (just before the 7th vial is poured), "... Blessed is he that watcheth, and keepeth his garments, lest he walk naked, and they see his shame. And he gathered them [see verse 14?] together into a place called in the Hebrew tongue Armageddon" (these [those who heed His Word] apparently having obtained, in/during the trib, that which was previously lacking, just as Revelation 3:18 had instructed...)]
That's kind of how I see it.
1) in the churchES, there exists both believers [saints] and those who are not [genuine saints]; whereas "the Church which is His body" consists ONLY of believers/saints [of 'this present age'... from the first century, up to our Rapture]
2) both "hot" and "cold" seem to be positives, from God's perspective (for it says, "I would thou wert hot or cold")
3) it is my understanding that "hot" and "cold" were waters originating from a particular source, whereas "lukewarm" was that which was not connected with such a source (sort of like a stagnant mudpuddle versus a river/stream [or aqueduct] or hot-springs kind of thing); thus, God "spews out of His mouth" the "lukewarm" who are not connected with the source: that is, He is looking to taste "Christ" in them, and lacking that, spews them out. So I tend to believe the "lukewarm" are those [in the churchES; i.e. in Christendom] who come in His name, but who are not vitally connected with/to The Source (Jesus Christ) [even Matt7 says some will say, "haven't WE DONE... many wonderful works" IN THY NAME, and He says unto them "I never knew you"]… IOW, I do not see the Rev3 passage as a "lose your salvation" context
[note: I tend to believe the "lukewarm," here, then are spewed into the tribulation period and there counseled to "buy of Me gold tried in the fire" 3:18, where also it says, "...that the shame of thy nakedness do not appear," which is very close to what is also stated in Revelation 16:15-16 (just before the 7th vial is poured), "... Blessed is he that watcheth, and keepeth his garments, lest he walk naked, and they see his shame. And he gathered them [see verse 14?] together into a place called in the Hebrew tongue Armageddon" (these [those who heed His Word] apparently having obtained, in/during the trib, that which was previously lacking, just as Revelation 3:18 had instructed...)]
That's kind of how I see it.
