Jude was compelled to warn his readers of the enemy’s attempt to neutralize the church from within by inserting false believers into the congregation. The very nature of the Christian faith demands that believers extend loving and welcoming gestures toward all sinners, following the example of Christ (Mark 2:15–17). Such a desire to reach people with the gospel and bring them to Christ, however, has a great negative aspect—failure to determine carefully the sincerity of those showing interest. Sadly, some “interested” people have wicked designs to harm the body of Christ. This is why Jude writes his epistle and does so with such intensity.
It is without question that many churches in this modern age have long ago become utterly devoid of spiritual power. In the words of the Puritan, Thomas Manton, “We think to fill the church, but we do but fill the house with thieves: wicked men ever prove a trouble.” These “thieves” are robbing the church of its spiritual power and kingdom influence in the community. This tragedy has occurred because the church in its zeal to increase numbers has abandoned careful examination of inquirers. Then, in order to keep them, the church no longer practices discipline (Titus 1:7, 8). Paul warned, “a little leaven leavens the whole” (Galatians 5:9).
Scripture points us to what a true church looks like in this respect. In Acts 5 a couple, following the example of Barnabas (Acts 4:36, 37), sold a parcel of land and gave the proceeds to the church. Their motive, apparently, was to get the recognition showered on Barnabas for his godliness. Tragically, Ananias and Sapphira were not doing what they did in obedience to Christ. Their spiritual poverty was apparent because greed tempted them to lie to the church and retain a portion for their own use. The land was theirs. They did not need to sell it nor did they need to give the money at all. Their whole design was to appear falsely as spiritual people in order to impress the church.
Because the church was spiritually vital, the Spirit of God was free to work mightily. Ananias and his wife were quickly exposed and suffered punishment from God. The bottom line is found in verses 13 and 14: “None of the rest [those like Ananias] dared join them, but the people held them [the true spiritual leadership] in high esteem. And more than ever believers were added to the Lord, multitudes of both men and women.”
The question we must ask is why God allowed these ungodly people to operate within the body? Jude plainly states that “they were before ordained to this condemnation.” They crept in unnoticed by the church but not unnoticed by God. They were His agents to provoke watchfulness in the body, a watchfulness attended by earnest prayer and careful observation. Christ commended the Ephesian saints for “testing those who call themselves apostles and are not” (Revelation 2:2). On the other hand, Thyatira is called out because the church “tolerate[d] that woman, Jezebel” teaching “the deep things of Satan” (Revelation 2:20, 24). Jude is earnest that his readers also be watchful, “praying in the Holy Spirit” (Jude 20; see Mark 14:38).