To objectively assess which contemporary religious group most closely aligns with the fundamental principles of early Christianity as taught by Jesus and the apostles—prior to later theological developments—it is necessary to evaluate various groups based on scriptural fidelity in doctrine and practice. The groups most commonly discussed in this context are:
- Jehovah’s Witnesses
- Seventh-day Adventists
- Anabaptist descendants (e.g. Amish, Mennonites)
- Church of Christ (non-instrumental)
- Christadelphians
- Mainstream Evangelicals / Protestant denominations
- Roman Catholicism and Eastern Orthodoxy