Well, of course the original miscalculation as to when 6,000 years of man's existence ended was god's fault, not WT's. WT was using a "flawed" King James Bible...the Bible being God's Word, which He apparently didn't correct for his chosen true religion:
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***Salvation book chap.16 p.287 par.12***
According to an inaccurate chronology that had been worked out from the King James Authorized Version Bible, Russell calculated that Christ’s "presence" had begun in the year 1874 C.E., *
unseen to human eyes and seen only by the eye of faith. This was why, when he began publishing a new religious magazine in defense of the ransom sacrifice of Jesus Christ, Russell entitled it "Zion’s Watch Tower and Herald of Christ’s Presence." *
* if Russell was the Faithful Slave, wouldn't God or Jesus have informed him the KJ was wrong before allowing Russell to teach the wrong date for Jesus' return for over 50 years? Or, did God not know that the KJ Bible was wrong and, therefore, didn't know any more than Russell and couldn't correct him?
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***w74 8/15 pp.506-507***
In 1877, Russell joined Nelson H. Barbour in publishing the book Three Worlds, and the Harvest of This World. It indicated that the end of the Gentile Times in 1914 would be preceded by a forty-year period to open with a three-and-a-half-year harvest beginning in 1874 C.E. According to Bible chronology thereafter adopted, it was understood that 6,000 years of man’s existence on earth ended in 1872, whereas six millenniums of human sin concluded and the seventh millennium began in 1874. Christ’s presence was thought to have begun in October 1874, at the start of the great antitypical Jubilee.—Lev. chap. 25; Rev. 20:4.
"According to trustworthy Bible chronology six thousand years from man’s creation will end in 1975, and the seventh period of a thousand years of human history will begin in the fall of 1975 C.E." —Life Everlasting – In Freedom of the Sons of God, 1966, p. 29
