In Matthew 24:42-51 Jesus talks about a faithful slave and an unfaithful slave. Since 1881 this has been a key doctrine. It is thought that their church is God's faithful slave and channel of communication to the world in these last days before armageddon.
The fact of the matter is that the meaning of Matthew 24:42-51 about the faithful/unfaithful slave is unknown. Any interpretation of what it means is an opinion or guess. However let's assume that the Watchtower is God's slave. Is God's slave faithful or unfaithful? The Bible gives us two clues about the identity of the unfaithful slave.
The unfaithful slave 'beats' fellow servants of the 'master'. See the Watchtower Sept 1, 1989
The unfaithful slave takes pleasure with those who are overcome with wine. Matthew 24:49 Are the beliefs of Jehovah's Witnesses based on reality and what the Bible really says? Or are they spiritually drunk and living in a fantasy world? Why is it that Christian religions and Bible scholars disagree with the Watchtower and visa versa? Who has 'the truth'? Is it possible that every single religion on the planet today is wrong about everything and only Jehovah's Witnesses understand the Bible correctly? Would a sober person believe such a thing?
When referring to the unfaithful slave, Jesus said that the master will 'cut him to pieces and assign him a place with the hypocrites, where there will be weeping and gnashing of teeth.'