I like this paragraph from the German theologian Karl Barth in 1948.
“What objection could we really make if it should please God to carry his work onward and reach his goal, not through a further numerical increase but through a drastic numerical decrease of so-called Christendom? It seems to me the only question in this matter is: How can we free ourselves from all quantitative thinking, all statistics, all calculation of observable consequences, all efforts to achieve a Christian world order, and then shape our witness into a witness to the sovereignty of God’s mercy, by which alone we can live-a witness to which the Holy Ghost will surely not refuse his confirmation?
Barth was commenting on the papers prepared for the first Assembly of the World Council of Churches in Amsterdam of that year in his essay entitled “NO CHRISTIAN MARSHALL PLAN,” in The Christian Century, December 8, 1948.