Why church membership? I was going to write a post on it, but I thought this short video by Christian rapper / pastor Trip Lee sums it up nicely (but without rapping):
If you aren’t yet a member of our church, please contact us to chat further about it. Unlike some churches, we do not require those who wish to be members to be persuaded by the secondary theological distinctives we hold to (such as the baptism of believers’ children). Rather, the main requirement for membership is to be a genuine Christian believer who is willing to submit themselves to the elders of the local church. As our Book of Church Order puts it:
3.2.01. Admission to communicant membership of a local church is by action of the session. It is open to baptised persons who make a credible profession of faith in the Lord Jesus Christ; who are believed to have been regenerated; whose Christian profession is not contradicted by flagrant sin or a denial of fundamental Christian doctrines; who are willing to submit themselves to the government of the local church, and who have presented themselves to its session as a witness thereof.