“So they remained for a long time, speaking boldly for the Lord, who bore witness to the word of his grace, granting signs and wonders to be done by their hands” (v3). Paul and Barnabas “spoke boldly” in Iconium and later in Lystra, and their words were accompanied by powerful demonstrations of God’s reality. In Lystra, a lame man was healed (v10), causing a city-wide uproar. Paul and Barnabas worked hard to explain that the life-changing power was God’s, not theirs (v11-18).
“He did not leave himself without witness” (v17). Our witness of Jesus can’t be just words; God’s reality must be demonstrated visibly through changed lives.