Jon Anon said in post 1:
When will Elijah the prophet appear in the world?
Possibly mid-tribulation. For in Revelation 11:3-12, the two witnesses could be Moses and Elijah, because the two men seen "standing before the God of the earth" (Revelation 11:4) at the transfiguration were Moses and Elijah (Matthew 17:3). And in Revelation 11:4. the "two olive trees" refer back to the two men who were already standing by the Lord by the time of the prophet Zechariah (Zechariah 4:11,14), which was subsequent to the times of Moses and Elijah.
Moses and Elijah could come down from heaven in their mortal bodies at the midpoint of the future tribulation of Revelation chapters 6 to 18 and Matthew 24, just as they came down at the transfiguration. Also, the plagues that the two witnesses will cause (Revelation 11:6,5) will match plagues that Moses and Elijah caused in Old Testament times (James 5:17, Exodus 7:20; 2 Kings 1:10-14). Elijah never died, but was taken bodily into heaven (2 Kings 2:11b). And Michael retrieved Moses' dead body from Satan (Jude 1:9). Michael could have then taken Moses' body into heaven, where it could have been resuscitated back to mortal life, like, for example, Lazarus' dead body was resuscitated back to mortal life (John 12:1). This would explain how both Moses and Elijah could appear alive and well at the transfiguration (Matthew 17:3).
The two witnesses will prophesy and bring plagues on the world during the future, literal 3.5 years (Revelation 11:2b,3,6) of the Antichrist's worldwide reign (Revelation 13:5,7, Revelation 12:6,14), which will be in the latter half of the future tribulation of Revelation chapters 6 to 18 and Matthew 24. That's why the Antichrist's reign will legally end (Revelation 11:15) right after the time of the two witnesses on the earth will end (Revelation 11:12-15). The plagues that they will bring (Revelation 11:6) will be part of the tribulation's 2nd woe/6th trumpet (Revelation 11:14, Revelation 9:12-13). They will be taken up to heaven before the tribulation's 7th trumpet sounds (Revelation 11:12,15).
They may not be witnesses in the sense of evangelizing the world (Acts 1:8), for the original Greek word (martus, G3144) translated as "witnesses" (Revelation 11:3) can also refer to those who witness against people and bring punishment against them (Acts 7:58). The reason that there will be two witnesses (Revelation 11:3) who will bring plagues to torment the unrepentant world (Revelation 11:6,10b) would be because two witnesses are required to bring judgment against people (1 Timothy 5:19). At the same time, the two "witnesses" could be called that because both of them will be martyred (Revelation 11:7-9). For the same Greek word translated as "witnesses" (Revelation 11:3) can refer to "martyrs" (Revelation 17:6).
Jon Anon said in post 1:
When paul is speaking of 'the day of the lord' in 1 thessalonians 5:3 he says they will be saying peace and safety right before the day of the lord begins so it is a pre-tribulation time that Elijah arrives on the scene because Elijah will be sent "BEFORE" the day of the lord:
1 thessalonians 5:3:
For when they shall say, Peace and safety; then sudden destruction comes upon them, as travail upon a woman with child; and they shall not escape.
The day of the Lord/Christ (2 Thessalonians 2:2) will begin at the Lord Jesus Christ's 2nd coming (1 Corinthians 1:7-8; 2 Thessalonians 2:1-8; 2 Thessalonians 1:7-10), which won't occur until Revelation 19:7 to 20:6, "immediately after" the future tribulation of Revelation chapters 6 to 18 and Matthew 24 (Matthew 24:29-31; 2 Thessalonians 2:1-8), which is when the rapture will occur (Matthew 24:29-31; 2 Thessalonians 2:1-8, Revelation 19:7 to 20:6).
1 Thessalonians 5:3 could include reference to when, near the end of the future tribulation of Revelation chapters 6 to 18 and Matthew 24, at the two witnesses' death at the legal end of the Antichrist's 3.5-year worldwide reign (Revelation 11:8,15, Revelation 13:5-18), the unsaved world will rejoice and make merry, because it will then be free from the tormenting plagues from the two witnesses (Revelation 11:10,6). But little will the unsaved world realize that the plagues of the 7 vials of God's judgment and wrath will then be poured out upon it (Revelation 16). And then Jesus will return and bring the 2nd-coming judgment and wrath of God (Revelation 19:11 to 20:3).
The unsaved people of the world will have no idea that most of them are going to be killed at Jesus' 2nd coming until it happens (Matthew 24:37-39). For they could think that the 2nd coming had already occurred with the coming into power of the Antichrist's miracle-working False Prophet (Revelation 13:13-14, Revelation 19:20), who could claim to be Jesus returned. And just as the people of the world shortly before Noah's flood, even though they could see or hear about Noah building his huge ark, no doubt rejected the idea that YHWH had the power to actually cause a global flood which would kill them, so the people of the world at the end of the future tribulation could reject the idea that YHWH has the power to actually defeat them.
For during the tribulation's 2nd half, the world will see the power of Lucifer (Satan, the dragon) and his fallen angels (Revelation 12:9), and the power Lucifer will give to the Antichrist to take over the entire earth (Revelation 13:4-8), and to utterly revile YHWH year after year without being destroyed (Revelation 13:5-6, Daniel 11:36), and to physically overcome and kill people in the church in every nation (Revelation 13:7-10, Revelation 14:12-13, Revelation 20:4-6, Matthew 24:9-13). And the world will see the amazing miraculous powers that Lucifer will give to the Antichrist's False Prophet, by which he will be able to even call fire down from heaven in the sight of everyone (Revelation 13:13, cf. 2 Thessalonians 2:9).
And near the end of the future tribulation, the world will see the Antichrist's defeat of YHWH's amazingly-powerful two witnesses (Revelation 11:3-9), after which defeat the world will rejoice and make merry and send gifts to each other because the two witnesses had been sending plagues on the world (Revelation 11:10,6). And even though those plagues will be shortly followed by even more plagues from YHWH, poured out directly from heaven (Revelation 16, the tribulation's final stage), the people of the world won't lose their confidence that YHWH can still be defeated. For after almost all of the plagues from heaven are over, the world will see the amazing miraculous powers of some unclean spirits, convincing the world's armies to gather together for a battle against YHWH (Revelation 16:13-14, Revelation 19:19). And so the world could come to that battle at the very end of the tribulation with the same careless attitude as some people at the start of the American Civil War, who held picnics at the expected first battleground of Bull Run/Manassas to watch the battle and what they expected to be a quick and easy victory.
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Jon Anon said in post 6:
I believe jesus also said elijah " shall" come which is future tense
Matthew 17:11
That's right.
Matthew 17:10-13 can be understood as referring to two different comings of Elijah, the first being John the Baptist's coming "in the spirit and power of Elijah" (Luke 1:17, Matthew 17:12-13), and the 2nd being a still-future physical coming-back of Elijah himself, when he will restore all things (Matthew 17:11), in the sense of restoring all true doctrine, i.e. all true interpretation of the Bible (2 Timothy 3:16), to the church. This still-future, physical coming-back of Elijah himself could occur at the midpoint of the future tribulation of Revelation chapters 6 to 18 and Matthew 24 (Revelation 11:3-12).