No one needs to be a church member in order to attend the church’s worship services. There are many places where non-members can happily serve and participate outside of Sunday morning. The local church is not like a private golf course where you need to be a member, dress a certain way, and pay your membership dues in order to participate. But does this mean that church membership is unimportant and optional?
The Bible doesn’t contain a verse specifically commanding church membership, but Scripture routinely assumes that the people of God will gather together and be committed to each other. The early Christians did not have the ability to “church shop” or have a casual relationship with their local church. In the same way, Christians who live in the midst of persecution find themselves needing to choose whether or not they’re “in” or they’re “out” of the church, the family of God.
There is a growing trend in American Christianity to minimize church membership. It is certainly possible to be a genuine Christian who is not a member in a local church, but there are many reasons why it is healthy and good for every Christian to be a member in their local church.
Living Theologically 