Is it right for churches to require a formal membership, with membership vows? I don’t see this present in the N.T. I am committed to my local church but am not sure about coming into membership.
You are correct in observing that the New Testament does not mention this issue. For what it’s worth, my own opinion is that there’s nothing wrong (in the sense of sinful or immoral) with a local body requiring formal membership. Many churches do require a formal membership before allowing people to participate in voting on matters affecting the church, or serving in positions of church leadership, etc. Oftentimes, the reasoning here is that only people committed to this local body of believers and in agreement with the church’s doctrinal statement, etc., should be allowed to share in the leadership decisions of the church. Since most local churches have some unbelievers, or uncommitted attenders, membership requirements help prevent those who might not be qualified to share in church leadership decisions from helping to make such decisions. Thus, for many churches, membership requirements may serve a sort of safeguard for doctrinal purity and godly decision-making.
Of course, a church should never refuse to minister to those who decline becoming members. And there may be some (like yourself) who are deeply committed to the church, but do not wish to embrace formal membership. The NT does not require one to take formal membership vows to a local church, etc. All who put their faith in the person and work of Christ are members of the universal church, even if they don’t want to become formal members of a local church. And I don’t think there’s anything wrong with such a decision.
Thus, as long as the motives for doing so are good and pure, I don’t think it’s wrong for a church to have a formal membership procedure. However, I also don’t think it’s wrong for a true believer in Christ to freely choose not to become a formal member of a particular local body.
This, at any rate, is my opinion. I hope it’s a little helpful.