Here are some snippets:
"It is easily forgotten that the fellowship of Christian brethren is a gift of grace, a gift of the Kingdom of God that any day may be taken from us, that the time that still separates us from utter loneliness may be brief indeed. Therefore, let him who until now has had the privilege of living a common Christian life with other Christians praise God on his knees and declare: It is grace, nothing but grace, that we are allowed to live in community with Christian brethren."
Speaking of communal worship:
"Where the heart is not singing there is no melody, there is only the dreadful medley of human self-praise. Where the singing is not to the Lord, it is singing to the honor of self or the music, and the new song becomes a song to idols."
"In a Christian community everything depends upon whether each individual is an indispensable link in a chain. Only when even the smallest link is securely interlocked is the chain unbreakable. A community which allows unemployed members to exist within it will perish because of them."