Recall the context of these verses in Mat 18:1-14, Mar 9:33-50, and Luk 9:46-50. While a number of Jesus’ followers had ceased to follow Him (Joh 6:66), His closest disciples had become even more convinced that He was the Messiah and that the establishment of His kingdom was imminent (cf. Peter’s confession and Jesus’ response in Mat 16, as well as the Transfiguration in Mat 17). However, as a result, they had become arrogant in their attitudes towards others and had argued among themselves which of them was the greatest. For this reason Jesus chastised them for their attitudes, warned them of the great danger of causing “little ones” in the faith to stumble, and expounded the great love of the Father who is not willing that even a single one of these little ones perish—even though they have strayed from the truth. What questions then naturally arise in this context in regard to such straying sheep? Think: Is it necessarily easy to convince an errant sheep of the danger it is in for having strayed away? What is the natural response of little ones who have strayed to those who would seek to restore them, and how is that response similar to what Jesus just warned them about? Cf. Mat 15:12 and NAS text note there. By warning His disciples about offending little ones and causing them to stumble, was He saying that we should just overlook their offenses and let them go their way?
What all is entailed by Jesus’ condition in Mat 18:15, “If your brother sins…”? Cf. Act 25:8 where the same Greek word is translated as “committed offense”. In the context of Mat 18:12-14, should we understand such offenses primarily in terms of sins against one another that alienate the offender from the offended, or sins against God that leave one alienated from Him? Cf. the NASB text note and observe that “against you” is found in many manuscripts, but not in the oldest and best. Is there a relationship between offenses against one another and offenses against God? Cf. Psa 51:title-4, 1Co 8:12. Are the offenses Jesus refers to by this word to be understood as the irritations or disagreements that often arise between believers? Is it significant that Jesus did not say, “If your brother annoys you…”? Is there a difference between a sin and an annoyance or disagreement? What is the difference? Give examples. Cf. Act 15:36-41, Col 4:10. The scriptural admonition for dealing with a brother who sins is found here in this passage; what is the scriptural admonition for dealing with a brother who is irritating or annoys us? See Rom 12:18, Eph 4:1-3, Phil 2:1-4, 4:2, Col 3:12-15, Jam 3:17-18, 1Pe 3:8-11. If a brother sins, who has a problem with God: him or us? If a brother annoys us, who has a problem with God: him or us? In what way is the response of Christians often the reverse of the scriptural admonition in dealing with the sins and annoyances of a brother? Think: are we more likely to remain silent when a brother falls into sin or when he annoys us?
What does Jesus say we should do if a brother sins, whether against us personally, or in general? See Mat 18:15. What does it mean to reprove him? See Joh 3:20, Eph 5:11,13 where the word means to expose, bring to light, and Joh 8:46, 16:8 where it means to point out or convict. In this light, should we understand that it is just the Holy Spirit working directly upon a person’s heart apart from others that convicts a person of their sin? See Luk 3:19, Tit 1:13, and consider that while David’s heart “smote him” unto repentance after cutting off the edge of Saul’s robe (1Sa 24:5) and numbering the people (2Sa 24:10) indicating the direct work of the Spirit, the same did not happen in regard to his sin with Bathsheba and against Uriah until Nathan the prophet exposed it and reproved him (2Sa 12:1-13).
Did Jesus say in Mat 18:15 that when anyone sins we should go and reprove them? See the context of Mat 18:12, and cf. Pro 9:7-8, Mat 7:6, 1Co 5:9-13. Did He say that when a brother sins we should just ignore it as if nothing happened because it isn’t our problem, or it doesn’t really matter because God will forgive him anyway since he can’t lose his salvation, or we should wait for him to come to us when the time is right after the Spirit has already brought conviction? When a brother wanders away from the truth and strays into sin, why is it not just his problem, but also our own? See 1Co 5:6, 12:20,26a, and consider that the church is a covenant community, which is why its members are called brothers. As such, we have a responsibility both for the well-being of the community itself and for each member who is a part of the community; cf. Jos 9:3-6,11,14-21, 10:1-7, Lev 19:17, Eze 34:1-6, Gal 6:1-2, Jam 5:19-20.