All Scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness, that the man of God may be complete, thoroughly equipped for every good work – 2 Timothy 3:16-17
This is illustrated in the story of Philip and the Ethiopian . Jesus taught His disciples the Scriptures. He opened their minds so they could understand the Scriptures. When He was here on earth, taught the Scriptures, rebuked those who were unbelieving and even those close to Him (Thomas, Peter and Philip), He corrected people like the adulteress, Nicodemus and the disciples. The apostles did the same. They taught. Peter rebuked Simon, the Sanhedrin, Ananias and Sapphira. Paul rebuked the churches that were allowing themselves to be led astray by false teachers. Stephen rebuked the Sanhedrin. There are many examples of the apostles rebuking people and even each other. They corrected unrighteous behavior and they trained others. Paul instructed Timothy who was young (1 Timothy 4:1:15).
Paul knows the Scriptures. He said Scripture has confined all under sin, that the promise by faith in Jesus Christ might be given to those who believe (Galatians 3:22). It was Paul who said that all Scripture comes from God as it is useful for teaching people, rebuking doubt, disbelief, false teachings, unrighteousness, etc., correcting attitudes, beliefs, behavior that goes against the Word of God and training those who believe so that those preaching the Word of God are able to do so. This is how the Gospel will spread. Those who receive the Word like the Samaritan woman, the apostles will go and tell others. It is in the teaching, receiving of the Scriptures, the rebuking and the correcting that make people repent and accept Jesus Christ as their Lord and Savior. They receive salvation and are baptised. It was the reading of the Scriptures and the teaching of them that led the Ethiopian to accept Jesus and receive salvation. Then he was baptised by Philip. God knew that the Ethiopian was ready to receive Jesus in his life and that’s why He sent Philip.
Make sure that you not only use God’s Word to rebuke and to correct but to encourage (exhort), instruct. Do not get into a debate. Be patient and loving.