v1-2: Giving is often viewed as mundane, but it is important. Here are simple and clear instructions; 2 Cor 8-9 deals with the subject in greater depth.
v3: A gift was to be sent to Jerusalem, to support the Christians there.
v5-7: Paul shares his plans with the Corinthians. His wish is that he can spend some time with them, rather than make only a passing visit. All his plans were submitted to the Lord.
v9: Opportunity and opposition often go together. The apostle frequently saw significant numbers converted, but at the same time there were many enemies of the gospel. We must expect opposition whenever we see progress.
v10-11: Some had despised Timothy (see 1 Tim 4.12). Although a young man, he had grown in maturity, perhaps to the shame of others. Rather than rejoice in God's blessing upon him, they sought to bring him down.
v12: There was some difference between Paul and Apollos. Paul had strongly urged him to go to Corinth, but he was unwilling; but he remained a brother. We must have a gracious attitude towards those who do different things, and choose not to follow our advice.
v13-14: Closing commands. In difficult days we must be strong and faithful. Above all, do everything in love.
v15-18: Paul commends others who brought blessing and encouragement.
They devoted themselves to the blessing of others; unselfish attitudes.
Paul commends those who join the work, and who labour in it. Being a Christian requires such commitment. They supplied what was lacking; generosity was commended. They refreshed others. Again, in difficult times, when there are many burdens, we need such refreshment. v19-20: The churches evidently prayed for each other. v21-24: In closing, Paul adds his own personal greeting. He insists that true faith means that we love the Lord. Otherwise there is a curse. His prayers for grace and love are therefore truly for those who live the Lord.