A) We begin with Matthew 18:15, which presents a valuable strategy for Christians, especially those seeking maturity. Jesus instructs that if a believer sins against you, approach them privately and point out their fault. This advice warrants contemplation. It pertains to interactions between believers - brother to brother, sister to brother, brother to sister. If someone has wronged you, Jesus advises addressing the issue privately with that person, not broadcasting it on social media or through word of mouth. 

B) If nothing results from this private encounter, then it's time to involve other witnesses, but not before. If attempts to create peace prove unsuccessful (remember, the Bible blesses peacemakers), you should return with two or three people to confirm or witness the engagement. The purpose is not merely to support your side, but to ensure objective perspectives are present.

C) The situation escalates at this point. If two people, along with two or three others seeking to help them reconcile, cannot achieve peace due to stubbornness, the issue has escalated. This indicates an unwillingness to forgive, cooperate, and embody Christ-like behavior. Consequently, the matter should be brought before spiritual authority, not to punish the transgression, but to facilitate reconciliation and unity.

D) If a person refuses to exhibit Christ-like character, remains unyielding, defiant, and full of pride, Jesus instructs us to treat that person like a pagan or a corrupt tax collector. It's crucial to understand that the goal is unity, grace, mercy, and love. However, if individuals identifying as Christians refuse to adhere to these principles, they demonstrate their estrangement from their king.