1 Corinthians 16:7

For I will not see you now by the way; but I trust to tarry a while with you, if the Lord permit (KJV)

Then: Finally Paul brings in the Lord. All planning needs submitted to him. His servants must be ever ready to change and use new opportunities or deal with barriers. This is a quick reminder.

Now: Using 2 Corinthians 2:1-4 Baker (p. 244) discusses how radically Paul's plans changed. After making a direct, but not-so-great quick trip to Corinth, he returned to Ephesus, wrote them a severe (missing) letter, and settled on his original plan of going up through Macedonia.

Extra Source: Cornerstone Biblical Commentary 1 Corinthians (William Baker), 2 Corinthians (Ralph Martin & Carl Toney), ed. by Philip Comfort. Carol Stream: Tyndale House Publishers, c2006.