It would appear that God did not directly reveal every place that Barnabas and Paul would preach the gospel. Sometimes the next course of action was evident by the opposition they faced. Sometimes God providentially directed their course, as when Paul and Barnabas strongly disagreed and went their separate ways (Acts 15:36-41). Sometimes God guided by closing doors to ministry (Acts 16:6-7). And then there were the rare occasions when God spoke directly (that is, through a vision) to reveal where they should go.
My point is that we should look for divine guidance from a variety of indicators. First and foremost, we should be guided by the Word of God. The Great Commission (Matthew 28:18-20; Acts 1:8) is a very clear revelation of God’s will. Sometimes circumstances (open and closed doors) will indicate the path or course of action we should take. Sometimes God guides through the painful events of our lives, as when He guided Paul to take Silas as a partner and Timothy as his helper. The fact is that when all is said and done, God’s will is accomplished, in a way that glorifies Him and not men. The good news for Christians is that even though men fail, God’s purposes and promises are always fulfilled.
It is with great sadness that I read our text and see Paul and Barnabas parting ways. But it is with great joy and confidence that I see how God used this unpleasant parting to achieve His gracious purposes. To God be the glory!