What does it mean to have fellowship among believers?

Fellowship among believers is crucial to the Christian life, as it represents a shared commitment to the truth of the gospel and the doctrines of Christ. In 2 John, John highlights the importance of recognizing true believers based on their adherence to sound doctrine, particularly concerning the nature and work of Jesus. True fellowship is not merely social interaction but is rooted in a common faith in Christ's person and His work of redemption. Believers are called to encourage one another in this truth, support one another in love, and be vigilant against false teachings that can undermine such fellowship. John warns that accepting those who deny these doctrinal truths jeopardizes this fellowship and can lead to a loss of rewards promised by God to His faithful followers.