Jehovah's Witnesses proclaim the good news of the kingdom under the power of God's holy spirit. Jesus commanded his followers to preach in the most distant parts of the earth and promised them that the spirit of God would guide them in this life-saving work (Acts 1:8).
Without the spirit of God, one cannot continue preaching about Jesus and God's kingdom (Matthew 24:14). One surely will not have God's spirit if one preaches a negative message (against Jehovah's servants) from door to door. One also cannot preach without loving God and neighbor. That is why you will never see jw opposers out preaching from door to door. It is a divinely supervised work that is a mark of true Christianity. Only true Christians can faithfully carry out this work.
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