From the article Confidentiality in the Church: What the Pastor Knows and Tells, by D. Elizabeth Audette.
A recent survey I conducted of 300 Congregational clergy and laity uncovered some assumptions about confidentiality. No members of the group articulated ecclesial or theological grounds for their assumptions. Instead, their views were informed by a therapeutic model. Both clergy and laity regarded the clergyperson as a counselor, along the lines of secular counselors or psychologists. Confidentiality, then, became a matter of professional (counseling) ethics—with one difference. Unlike secular counselors or psychologists who see clients in well-defined professional settings, most of those surveyed assumed that anything told to a clergyperson anywhere should be treated confidentially, regardless of the circumstances of the disclosure.
… When therapeutic norms borrowed from professional ethics (as serviceable as they might be) become dominant in the church, the unique character of the church as a gathered people covenanted in Christ is compromised. The therapeutic ethic relies largely on a contract model of a professional-client relationship: confidentiality is based on the dual needs of respecting the individual and preserving the character of relationships. This approach does not encourage the appropriate sharing of information within the community by which the gathered people might be responsible to and for each other.
While clergy at times counsel individuals, they also bear responsibility for the welfare of the worshiping community as a whole. … The church is a community with its own culture and beliefs, transcending the individuals within it and creating a common good. An ethic of confidentiality grounded in ecclesiology will care for the good of the community as well as the good of the individuals within it.