They pursue discipline for any reason other than for the good of the individual, the good of the church, the good of the onlooking community, and the glory of Christ.

Jonathan Leeman, “Appendix: Mistakes Pastors Make in Practicing Discipline,” Church Discipline: How the Church Protects the Name of Jesus (9Marks; Wheaton: Crossway, 2012), 139–40:

Pastors sometimes make the following mistakes regarding formal church discipline.

1. They fail to teach their congregation what church discipline is and why they should practice it.
2. They fail to practice meaningful membership, which includes (1) teaching people what membership entails before they join; (2) encouraging casual attenders to join; (3) carefully interviewing everyone who wants to join; (4) giving regular oversight to all the flock; and (5) maintaining an up-to-date membership list that accurately reflects who is present at the weekly gathering.
3. They fail to teach their congregation about biblical conversion, especially the need for repentance.
4. They fail to teach new members as they enter the church about the possibility of church discipline, and that preemptive resignations don’t work.
5. They fail to ensure that the church’s public documents (bylaws, constitution, articles of incorporation, etc.) address the procedures of church discipline, thereby exposing the church to legal risk.
6. They fail to follow the steps of Matthew 18 or 1 Corinthians 5, depending on the circumstance. In a Matthew 18 situation, for instance, they fail to begin the process by confronting sin privately.
7. They misjudge how quickly to move toward formal discipline, either by dragging their feet or by rushing into judgment.
8. They fail to adequately teach and explain to a congregation why a particular act of discipline is necessary.
9. They tell the congregation too many details about a particular sin for which they are recommending discipline, embarrassing family members and causing weaker sheep to stumble.
10. They treat the processes of church discipline entirely as a legal process with little consideration for shepherding the unrepentant individual’s heart.
11. They give little attention to the differences between kinds of sinners and how that might affect how long a church should bear with a pattern of sin before proceeding to subsequent stages of discipline (see 1 Thess. 5:14).
12. They forget that they too live by the gospel’s provision of mercy, and therefore prosecute the discipline from a posture of self-righteousness. Other mistakes follow from this wrong posture, such as an overly severe tone and standoffishness.
13. They fail to truly love the sinner . . . by not begging the Lord for his or her repentance.
14. They demand too much from a smoldering wick or bruised reed. In other words, their stipulations for repentance are too high for someone who has been deeply enslaved in sin’s grip.
15. They fail to properly instruct the congregation on how to interact with the unrepentant sinner, such as how to relate to him or her in social situations and how to pursue his or her repentance.
16. They fail to invite the disciplined individual to continue attending services of the church so that he or she might continue to hear God’s Word (assuming there is no threat of criminal harm). Also, they fail to inform the church that everyone should hope for the disciplined individual to continue attending.
17. They put the responsibility for leading the discipline process entirely on the shoulders of one man, the senior pastor, thereby tempting individuals in the church to accuse the senior pastor of being personally vindictive.
18. They fail to have sufficient elder involvement in the congregation’s life, such that the elders are unaware of the state of the sheep. This failure of formative discipline will inevitably weaken the church’s ability to do corrective discipline well.
19. They fail to teach God’s Word on a weekly basis.
20. They allow the congregation to approach a case of discipline with a wrongful spirit of retribution, rather than with the loving desire to warn the unrepentant sinner about God’s ultimate retribution to come.
21. They pursue discipline on nonbiblical grounds (playing cards, dancing, etc.).
22. They pursue discipline for any reason other than for the good of the individual, the good of the church, the good of the onlooking community, and the glory of Christ.

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