Christians ought to strive to achieve God’s ideal plan for the church. This involves the individual Christian submitting to the authority of a local church, and the church covenanting with each Christian to protect and guide.
While it may be possible to perform the act of baptism or communion outside of local church membership, it is doubtful whether those actions truly demonstrate what the ordinances are intended to reflect.
In order for the church to fulfill the Great Commission, it is not sufficient to evangelize others, but they must be added to the church.
Augustine’s position characterized the church for more than one thousand years with little mainstream opposition, and few, if any questioned the value and necessity of being joined to a church.
In today’s church the individual acts more like a consumer choosing to join whatever church offers the best benefits, or all too often choosing not to join a church while still enjoying the activities and benefits afforded by regular attendance.