Separation is scriptural under a variety of different scenarios. Most commonly, believers understand that they are to separate from unbelievers (2 Corinthians 6:14). This does not imply that believers should not witness to the lost but that there should be no “fellowship” between the two. The Bible also indicates that there are times in which one believer should separate from another believer. Most often, this happens because of the propagation of false doctrine (Romans 16:17-18; 2 Thessalonians 3:6) or immoral practices (1 Corinthians 5:11). However, there may also be instances when believers separate for the purpose of furthering the work of God (Galatians 2:6-9).
It is much easier to serve God together with others rather than alone. There is great wisdom attained through the right kind of fellowship with other like-minded believers. When one believer wavers during times of temptation, his “fellow” believers will encourage him to stay faithful to the Lord’s work. When one of the saints struggles in times of uncertainty, his fellow believers can remind him of God’s faithfulness. The Bible shows us that the early church thrived in the Lord’s work. Those early Christians served the Lord with a great zeal. The secret to their success most definitely included their continuation in fellowship and incorporating some basic principles. For instance, the Lord Jesus sent out His disciples by twos (Mark 6:7) and the early church followed suit (Acts 13:2). God has given us a great insight into the importance of fellowship by emphasizing it so frequently.
