The reason why vulnerability in Christian community is a good for us:
The Bible is filled with stories of people who were real Bozos. The people listed in the hall of fame in Hebrews 11 were real people with real problems, yet God lists them as models for us to emulate. God has never looked for perfect people, just faithful ones. The biblical standard is not people who have never failed; it is people who, when they failed, get reconnected to God and went on in faith. All of us should be comparing ourselves with this standard, not the one of perfection. Resolving guilt and shame always involves getting people to see themselves as fellow strugglers instead of super humans. As Paul says, we experience nothing that is not in some way common to humankind (1 Cor 10:13). The problem is that in our isolation, we rarely find out that what we experience is common.
--Cloud & Townsend, How People Grow