The following is one of the great passages from Bonhoeffer's Life Together:
If we do not give thanks daily for the Christian community in which we have been placed, even when there are no great experiences, no noticeable riches, but much weakness, difficulty, and little faith--and if, on the contrary, we only keep complaining to God that everything is so miserable and insignificant and does not at all live up to our expectations--then we hinder God from letting our community grow according to the measure and riches that are there for us all in Jesus Christ. That also applies in a special way to the complaints often heard from pastors and zealous parishioners about their congregations. Pastors [and zealous parishioners] should not complain about their congregation, certainly never to other people, but also not to God. Congregations have not been entrusted to them in order that they should become accusers of their congregations before God and their fellow human beings. When pastors [and parishioners] lose faith in a Christian community in which they have been placed and begin to make accusations against it, they had better examine themselves first to see whether the underlying problem is not their own idealized image, which should be shattered by God. And if they find that to be true, let them thank God for leading them into this predicament. But if they find that it is not true, let them nevertheless guard against ever becoming an accuser of those whom God has gathered together. Instead, let them accuse themselves of their unbelief, let them ask for an understanding of their own failure and their particular sin, and pray that they may not wrong other Christians. Let such pastors, recognizing their own guilt, make intercession for those charged to their care. Let them do what they have been instructed to do and thank God.
Like the Christian's sanctification, Christian community is a gift of God to which we have no claim. Only God knows the real condition of either our community or our sanctification. What may appear weak and insignificant to us may be great and glorious to God. Just as Christians should not be constantly feeling the pulse of their spiritual life, so too the Christian community has not been given to us by God for us to be continually taking its temperature. The more thankfully we daily receive what is given to us, the more assuredly and consistently will community increase and grow from day to day as God pleases.
Christian community is not an ideal we have to realize, but rather a reality created by God in Christ in which we may participate. The more clearly we learn to recognize that the ground and strength and promise of all our community is in Jesus Christ alone, the more calmly we will learn to think about our community and pray and hope for it." (pages 37-38 of the Bloesch/Burtness translation)