It's a Matter of Trust
Anyone with any experience in counseling will tell you that it is absolutely essential for the participants and their counselor or therapist to develop a rapport. Much of that is based on the ability of those involved to trust one another to be honest and to have everyone's best interests in mind. Christian family counseling facilitates the development of that trust. Those who share a faith are more likely to open up and to place their trust in one another.
Sharing Common Ground
In addition to the issue of trust, Christian family counseling also facilitates positive communication by insuring that the participants and their counselor share significant common ground in terms of their experiences and their broader outlook on the world. That makes the family more comfortable and allows them to enter the process with a sense that everyone is "speaking the same language" and that the therapist's goals are similar to those tightly held by the family members. This can be extremely powerful as people work through difficult issues.
The Power of Faith
Many Christians will take the position that working from a position of faith in an environment supportive and understanding their convictions will increase the opportunity for successful change. While non-believers may write that sentiment off as some kind of placebo effect, there's very little doubt that it's true to those who do have a strong faith life. Regardless of one's sentiments, that can't be ignored. From the perspective of many Christians, there is room for miracles and these diving breakthroughs may be more likely when people of a like perspective work together, asking for God's help and guidance as they deal with problems.
Those are three reasons why those who do have a strong Christian belief structure may want to consider Christian family counseling services when dealing with their family issues. There's nothing wrong with secular approaches, which have been proven to offer potential for people with strong convictions, but there is a great deal to be said in support of the utilization of service providers who share a similar life and religious outlook with their clients.