The Church acts as a sort of embassy for the government of the King. It is an outpost of the Kingdom of God surrounded by the kingdom of darkness. Just as an embassy is meant to showcase the life of a nation to the surrounding people, so the Church is meant to manifest the life of the Kingdom of God to the people around it.
Kevin DeYoung, What is the Mission of the Church?: Making sense of social justice, Shalom and the Great Commission
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