Paul repeatedly teaches that salvation is not earned through works that people do (Rom. 4:4-8; Eph. 2:8-10; Titus 3:5-6). A focus on this teaching, however, has led many to overlook an equally important Pauline evangelistic teaching concerning works: Paul emphasized that in his evangelism of all people everywhere, he challenged them that sinners must “do works meet for repentance” (Acts 26:20).
Peterson explains this emphasis well:
Paul recalls the geographical scope of his mission, ‘first to those in Damascus’ (cf. 9:20-25), ‘then to those in Jerusalem’ (cf. 9:26-30) ‘and in all Judea, and then to the Gentiles’. He indicates that he conveyed the same message to all, declaring (apēngellon, ‘reporting’, ‘announcing’, ‘proclaiming’) ‘that they should repent and turn to God and demonstrate their repentance by their deeds’ (cf. 20:21). Challenged to preach repentance for the forgiveness of sins and a share in the messianic salvation …, Paul was as serious as John the Baptist in calling for deeds to demonstrate the genuineness of repentance (cf. Lk. 3:8; Acts 20:21). He understood conversion ‘not only in terms of forgiveness and faith, but also in terms of a full ethical transformation’
—David. G. Peterson, The Acts of the Apostles in PNTC, 670
Based on Paul’s testimony to this crucial emphasis that he had in his evangelism, we should be diligent to challenge the people to whom we witness “that they should repent and turn to God, and do works meet for repentance” (Acts 26:20).