Expound, Testify, Convince

Luke uses several interesting words to describe Paul communicating the gospel of Jesus Christ to the Jewish community in Rome (Acts 28.23). He writes: When they had appointed a day for him, they came to his lodging in greater numbers. From morning until evening he expounded to them, testifying to the kingdom of God and trying to convince them about Jesus both from the Law of Moses and from the prophets.

"To expound" means "to convey information by careful elaboration," so Paul took all day, and we are probably talking 10 to 12 hours, to try and get his hearers to understand his message; that Christ was the Messiah and the fulfillment of the Tanakh (OT Scriptures). This is why we refer to the elucidation of the Scriptures to an audience as "expounding" the text; and why we teach expositorily. We are trying to convey information from the Scriptures by careful elaboration.

"To testify is "to make a serious declaration on the basis of presumed personal knowledge." This is not to imply that Paul had secret knowledge or knew more than his hearers. He had a new application for them by the personal knowledge of Jesus Christ and the events surrounding his life and death, and their application to the Tanakh.

Finally "to convince" is "to convince someone to believe something and to act upon that belief." One can see how good the word is that Luke chooses. Paul wasn't calling the Jews in Rome to an intellectual understanding of the Scriptures; he was calling them to a belief that would rock their world and change the way they lived.