'Testifying' in the Bible

but when Silas and Timothy came down from Macedonia (northern Greece), Paul began devoting himself completely to [preaching] the word, and solemnly testifying to the Jews that Jesus is the Christ (the Messiah, the Anointed).

But I have had help from God to this day, and I stand [before people] testifying to small and great alike, stating nothing except what the Prophets and Moses said would come to pass—

When they had set a day for Paul, they came to his lodging in large numbers. And he carefully explained [Christianity] to them from morning until evening, solemnly testifying about the kingdom of God and trying to persuade them concerning Jesus, both from the Law of Moses and from the [writings of the] Prophets.