The two groups who can not be resurrected at the Rapture will be the Tribulation saints and the saints at the end of the Millennium.
To be clearer, it is the Great Tribulation saints ( left behind saints & former believers as well as new believer after the pre great tribulation rapture ) & then the saints that remain loyal to Christ after Satan's last rebellion.
What happens with the resurrected OT saints of the Millennium years will be amazing. They will be transported into the second new heavens and earth.
Still see them as resurrected to be with the firstfruits per Luke 13:24-30
That is unique. There is also an unbeliever type rapture.
"Two will be in a field and one will be taken and the other left behind?"
That is not about our rapture.
Luke 17:26-37 is the pre great tribulation rapture. Those taken away are done by a winglike flight and with hospitality for them to resort in.
The Greek word "sunago" shows how they are being "gathered" and that has to do with abiding saints.
If you will note these verses in context of what that message is about; believers are warned to be prepared to leave every thing behind, even your treasure on earth that you would not be tempted to go back for.
Luke 17:30 Even thus shall it be in the day when the Son of man is revealed
. 31 In that day, he which shall be upon the housetop, and his stuff in the house, let him not come down to take it away: and he that is in the field, let him likewise not return back.
32 Remember Lot's wife. 33 Whosoever shall seek to save his life shall lose it; and whosoever shall lose his life shall preserve it.
So it is a warning to believers to be ready & willing to leave before that fiery destruction comes on the earth.
Those taken up will be the tares Jesus spoke of. For the Millennium must begin with all believers who endured to the end
of the Tribulation.
grace and peace ..............
The tares are saints left behind to burn when that fire comes on the earth. That does not necessarily mean they are all unbelievers. After the rapture and the everlasting gospel by that first angel spreads it everywhere, there will be new believers before that fiery calamity comes.
Luke 12:40 Be ye therefore ready also: for the Son of man cometh at an hour when ye think not. 41 Then Peter said unto him, Lord, speakest thou this parable unto us, or even to all? 42 And the Lord said, Who then is that faithful and wise steward, whom his lord shall make ruler over his household, to give them their portion of meat in due season? 43 Blessed is that servant, whom his lord when he cometh shall find so doing. 44 Of a truth I say unto you, that he will make him ruler over all that he hath. 45 But and if that servant say in his heart, My lord delayeth his coming; and shall begin to beat the menservants and maidens, and to eat and drink, and to be drunken;
46 The lord of that servant will come in a day when he looketh not for him, and at an hour when he is not aware, and will cut him in sunder, and will appoint him his portion with the unbelievers. 47 And that servant, which knew his lord's will, and prepared not himself, neither did according to his will, shall be beaten with many stripes. 48 But he that knew not, and did commit things worthy of stripes, shall be beaten with few stripes. For unto whomsoever much is given, of him shall be much required: and to whom men have committed much, of him they will ask the more
. 49 I am come to send fire on the earth; and what will I, if it be already kindled?
See how those believers that were not ready but found in iniquity are left behind for why they are getting stripes? compare below for not running that race by looking to the author & finisher of our faith to help us lay aside every weight & sin daily.
Hebrews 12:1Wherefore seeing we also are compassed about with so great a cloud of witnesses,
let us lay aside every weight, and the sin which doth so easily beset us, and let us run with patience the race that is set before us, 2 Looking unto Jesus the author and finisher of our faith; who for the joy that was set before him endured the cross, despising the shame, and is set down at the right hand of the throne of God. 3 For consider him that endured such contradiction of sinners against himself, lest ye be wearied and faint in your minds.
4 Ye have not yet resisted unto blood, striving against sin. 5 And ye have forgotten the exhortation which speaketh unto you as unto children, My son, despise not thou the chastening of the Lord, nor faint when thou art rebuked of him:
6 For whom the Lord loveth he chasteneth, and scourgeth every son whom he receiveth. 7 If ye endure chastening, God dealeth with you as with sons; for what son is he whom the father chasteneth not? 8 But if ye be without chastisement, whereof all are partakers, then are ye bastards, and not sons. 9 Furthermore we have had fathers of our flesh which corrected us, and we gave them reverence:
shall we not much rather be in subjection unto the Father of spirits, and live? 10 For they verily for a few days chastened us after their own pleasure; but he for our profit, that we might be partakers of his holiness.