When it comes to answering this question, the JW's commonly confuse two related, but separate issues.
There is a big difference between saying:
“We know for sure who will survive”
versus
“We know for sure who will not survive”
JW’s have never said they know for sure who will survive. They have always allowed for the possibility that even some within the ranks of Jehovah’s Witnesses themselves will be found unworthy. This is what they mean when they say that only Jehovah reads hearts.
On the other hand they have been quite explicit for many, many years on the issue of who it can definitely be said will not survive. There are the obvious and generic categories like the “wicked” and the “unrighteous,” but the WTB&TS started going far beyond that many years ago.
For example, the 1941 book Children said on page 295:
This is strong proof that only those who are in Christ and those who are of the “other sheep” of the Lord, together with the “princes”, shall survive Armageddon. All others now on the earth will die at Armageddon.
The October 15, 1952 issue of The Watchtower on page 619 said that only those in “God’s organization” would survive.
“The Scriptures speak of the avenger’s blood being hot. The heart of Christ Jesus is indeed hot with righteous indignation against those who have willfully violated God’s covenant. Like Jehu, he will proceed furiously against his enemies. (2 Ki. 9:20) This indicates that there is an urgency about fleeing to the city of refuge, God’s organization, now…….How long must these remain in the city of refuge? Until the death of the high priest, or until after Armageddon, when the last of the priestly members of Christ’s body die to join their Lord in the heavenly realm. Until that time let all dedicated servants of Jehovah make known his merciful provision for sparing unwitting manslayers, and let all men of good will, lovers of righteousness, take advantage of the merciful provision of Jehovah by fleeing to these cities of refuge, God’s organization.”
The 1953 book New Heavens And A New Earth on page 311 was even more explicit:
This baptism into the Greater Noah is what will save now and during the destructive fiery baptism of this condemned old world, provided the ones baptized into him within the ark abide in him, keeping their good conscience through faith and loyal service to God. To survive Armageddon they must stay in the New World society.
The August 15, 1953 issue of The Watchtower on page 501 reiterated the same thought:
“For anyone to forsake the organized congregation of those who are destined to survive Armageddon means for that one never to get past Armageddon into the New World and its theocratic system. Like Noah’s family, we must now get into the ark all together!”
The April 15, 1956 issue of The Watchtower on page 250 claimed that association with even “good” unbelievers could cost you your life:
“A ‘good fellow’ may be good company. But is he theocratic company? If not, then shun him. Run only with those running the race. Remember the old proverb: “Birds of a feather flock together.” You may also recall the old story of the farmer’s swan that always swam among the cranes. The cranes were destroying the farmer’s crops. So he determined to shoot them. He killed the cranes and with them also his beautiful swan, his prize bird. Do not be caught at Armageddon like this beautiful but unfortunate swan.”
The July 1 1956 issue of The Watchtower on page 401 showed that putting off baptism as one of Jehovah’s Witnesses would be a fatal error:
“So each one of you undedicated persons has today the same freedom to choose, a choice of life or death. If you deliberately refuse to dedicate yourself to Jehovah God in this judgment day of his in which we now are living, your life will end at Armageddon, if not before, as a condemned sinner without right to life and even without hope of a resurrection.
The February 1 1957 issue of The Watchtower on pages 73 and 74 showed that it wasn’t enough to simply lead a good life --- JW doctrine was a life or death matter:
“We say that the true Christian faith is the sum of beliefs concerning Jehovah God and his kingdom as delivered to us by his chosen Seed, Jesus Christ, and his disciples. But do not the peoples of Christendom also believe the same Bible? Then why is it that they do not believe the same things that Jehovah’s witnesses believe? Do not think that this is merely a matter of opinion, of private interpretation. Do not think that one can believe whatever he likes so long as he leads a good life, or that doctrinal differences do not really matter. That is a fatal error. It is just that distinction that makes all the difference between one’s surviving Armageddon and one’s perishing along with the old world.”
The July 15, 1958 issue of The Watchtower on page 439 again stressed the importance of being part of the organization:
It is not less important either, as the following article shows, that, having found one’s place in the constellation of the New World society, one should faithfully remain in it if one hopes to survive Armageddon and live forever in eternal peace and happiness.
The May 15 1960 issue of The Watchtower on page 305 reiterated the importance of JW dedication and baptism as a prerequisite for surviving Armageddon:
“If one knows he should dedicate himself to God and be baptized and does not do so, the responsibility before Jehovah is the same as if he did. The man who makes a dedication and fails will not survive Armageddon, but neither will the man who postponed dedication and never took the steps to qualify him for life. Both will be equally dead. Why be in either class?”
The February 1 1961 issue of The Watchtower on page 89 again showed that at Armageddon there would be no third group. You were either part of the New World society or you were not.
“As the spiritual cloud that envelops the earth gets darker and darker, now is the time to come out to the light enjoyed by the New World society. This light of truth has been getting brighter and brighter since Christ’s heavenly enthronement in 1914. Jehovah God and Christ Jesus, “the kings from the rising of the sun,” are preparing to gather the nations to the great battle of Armageddon. There will be no neutral position in that battle, no place to hide.”
The January 15, 1966 issue of The Watchtower on page 47 showed that regular meeting attendance was also a requirement for survival:
“Are you one of these irregular attenders? Do you know of any who are succumbing to this danger? If so, it would be an evidence of love on your part to consider with them Jehovah’s counsel and admonition on associating regularly at congregational meetings……..There is no question about our association after Armageddon, but, unless we are associating now with God’s congregation, we will not be alive to enjoy association with him, his Son and his people after Armageddon.”
The June 1, 1972 issue of The Watchtower on page 326 was quite explicit that any associated with “Christendom” would not survive:
"Any associated with Christendom who survive the destruction of false religion in the “great tribulation” will not come through to any improved, long-lived future. They will experience only the fire of Jehovah’s anger and his symbolic “sword” of judicial execution in the final part of the “great tribulation,” the “war of the great day of God the Almighty” at the world situation called Har–Magedon.—Rev. 16:14-16; 19:11-21."
The November 15, 1983 issue of The Watchtower on page 24 flatly stated that no one besides the anointed or their companions, the great crowd would survive:
“The only flesh saved out of that “great tribulation” will be, as Jesus himself stated, the dedicated “flesh” of his chosen anointed ones and of their sheeplike companions. No others are counted righteous in Jehovah’s sight”
The September 1, 1989 issue of The Watchtower on page 19 was said basically the same thing, but hedged a little with the term, "Scriptural hope".
“Only Jehovah's Witnesses, those of the anointed remnant and the "great crowd," as a united organization under the protection of the Supreme Organizer, have any Scriptural hope of surviving the impending end of this doomed system dominated by Satan the Devil.”
The May 1, 1991 issue of The Watchtower said that no one associated with “Christendom would survive Armageddon in a particularly round-about way. First it said on page 14:
“Similarly today, “a great crowd” of Jesus’ “other sheep” gathered out of all nations will survive Armageddon into God’s new world. (Revelation 7:9; John 10:14-16) Only those who learn and speak the pure language will be joyful survivors.
….and then it said on page 16:
“Those who declare Jehovah’s purpose and announce his heavenly Kingdom speak the pure language as his Witnesses. They make known his name and serve him “shoulder to shoulder,” or with one consent. (Zephaniah 3:9) Though Christendom’s religions have the Bible, they do not speak the pure language or call upon God’s name in faith.”
Taken together, it was not hard to add 2 and 2.
The June 1 1992 issue of The Watchtower on page 16 quantified the “great crowd” of survivors as the number of active JW publishers:
“Last year the great crowd, now numbering more than four million, together with the small remaining band of anointed Christians, spent nearly a billion hours declaring abroad the excellencies of Jehovah. This was the best possible use of their spiritual freedom.”
The February 15, 1995 issue of The Watchtower on pages 14 and 15 did the same thing:
“Today, almost five million members of the great crowd are living under the active leadership of the heavenly King Jesus Christ. They are in subjection to Christ and in close association with his anointed brothers yet on earth.”
The July 1, 1995 issue of The Watchtower on page 21 did the same thing:
“Since then, the emphasis has been on gathering the great crowd of other sheep, which today numbers almost five million.”
The few non-committal statements the JW's have made do little to undo what their organization has taught for over 50 years.
