Jehovah's Witnesses are the true Christian congregation.
I know they are because they tell the truth and their core doctrines have not ever changed:
"Jehovah is the Grand identifier of his true messengers. He identifies them by making the messages he delivers through them come true. Jehovah is also the Great Exposer of false messengers."
MAY 1, 1997 WATCHTOWER
PAGE 8
http://www.jwfacts.com/images/g69_may_22p15.g...
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"Question. The fact that our Lord received worship is claimed by some to be an evidence that while on earth he was God the Father disguised in a body of flesh and not really a man. Was he really worshiped, or is the translation faulty? Answer. Yes, we believe our Lord Jesus while on earth was really worshiped, and properly so. It was proper for our Lord to receive worship in view of his having been the only begotten of the Father and his agent in the creation of all things, including man."
JULY 15, 1898 WATCHTOWER
PAGE 216
Trinitarians who believe that Jesus is God, or at least the second person of the triune God, do not like to have Jehovah’s witnesses say that it is unscriptural for worshipers of the living and true God to render worship to the Son of God, Jesus Christ.
NOVEMBER 1, 1964 WATCTOWER
PAGE 671