His point was that there is a difference between "church work" (i.e. work done to maintain the institution of "church" - e.g. boards, committees, nursery workers, worship leaders, etc.) and the "work of the church", in other words, those missional activities where the church is serving others outside it's four walls. The work of the church is the work of justice and compassion in the world. It is feeding the poor, liberating the oppressed, encouraging the broken hearted. And it is not simply "service evangelism" or even "friendship evangelism" whose ultimate goal is still just to get people to show up to church on Sunday and grow the institution. It is the work the church does as a part of helping God's will to be done "on earth as it is in heaven".
Not that I'm saying there's anything necessarily wrong with evangelism or with church work. If the "work of the church" is going to happen, that is, if people are going to be out in the world living lives of compassion and justice, then of course we need to both recruit them to that way of life (i.e. evangelism) and equip and prepare them to do it (i.e. through worship and teaching and fellowship). But we should be careful not to forget what those things are for, and risk letting them become ends in themselves, rather than means to the greater end of living missionally in the world as agents of God's kingdom. That's what it means to be "missional" in the first place. It means to stop thinking of mission as merely one more thing tacked onto everything else the church does, and to start seeing it as the central and defining reason for the church's existence, in support of which everything else is done.
So if 20% are doing 80% of the "church work" then that's a good thing, so long as that is actually freeing up the other 80% to be more engaged in the world around them doing the work of the kingdom. And while that is not necessarily a safe assumption yet, we ought to at least recognize that this is the goal, and not make the mistake of thinking that if we could only get more people doing "church work" that somehow that would be better.
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