1 Corinthians 9:26

I therefore so run, not as uncertainly; so fight I, not as one that beateth the air (KJV)

Then: The Corinthians who attended the Isthmian games lived in a time of individual, not team, competitions (Baker, p. 136). Avid fans could pick out which athletes were serious and which ones were just marking time. Paul locks into that knowledge to describe his own work for the Lord. He had his mind made up, knew what he had to do to be successful, and didn't just pretend to follow the Lord with "for-show" motions.

Now: The desire to win is strong in almost every individual. When channeled into the service of the Lord, results can be astounding. That's why many look at the work of Paul and wonder how can it be duplicated in today's world. Paul does not hide his strategy and beliefs. Those who emulate him can be just as fruitful in the Lord's work.

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

1 Corinthians 16:18

For they have refreshed my spirit and yours: therefore acknowledge ye them that are such (KJV)

Then: The place of Stephanos and company in the Corinthian church is debatable. N. T. Wright (p. 237) believes they were not necessarily aligned with the pro Paulites. For this reason Paul could rejoice in some, even those he'd baptized, looking past the party spirit to the greater purpose of keeping believers united in love, fully able to stand firmly on the Rock of Salvation. The joy in the verse illustrates Paul's delight in that hope for the Corinthian church. He wants the entire church to rejoice in and emulate those servants.

Now: When believers know a churches defects and work to improve it, they always face the same difficulty that Paul did - trying to make members aware of the strengths, not feel that the congregation is a lost cause, and be encouraged enough to work out the problems.

1 Corinthians 16:14

Let all your things be done with charity (KJV)

Then: The King James word for love is charity. That better matches and clarifies a Corinthian understanding of the word. It omits all the other meanings lumped into the English meaning of "love" (Magness class notes). In context, Paul is not letting his just stated admonitions be actions without value. Harking back to his earlier presentation of the way to live the Christian life, he gently reminds them again - Anything done without love has no value.

Now: Baker (p. 246) brings attention to other passages such as Phol 4:809 or 1 Thess 5:12-22 where Paul reviews what he's earlier spent extended time explaining. Since he already discussed it, he doesn't add anything more. It's also somewhat like a parent sending a child out the door, "Be good," expecting the offspring to remember former training.