This means: “Your glory will abound in me. For I will be present to see how your glory exults and abounds in Christ. I will see how you love Christ, how you serve Christ and how you rejoice in your service to Christ.”
What does he mean “that your boast may abound?” All there was to glory in was their being established in the faith. This is what it means to boast in Christ, to live rightly…. He means “so that I may have more to boast of in you…. As you improve, I have more to boast of.” .
You see that this explains the word abide with you. Behold his humility. Having said, for your progress, he shows that it was for his own profit too. This also he does, when he writes to the Romans, and says, That is, that we may be comforted together in you. Romans 1:11-12 Having previously said, That I may impart unto you some spiritual gift. And what means, That your glorying may abound? This glorying was, their establishment in the faith. For an upright life is glorying in Christ. And do you say, Your glorying in me, through my presence with you again? Yes, he answers; For what is our hope, or crown of glorying? Are not even ye? 1 Thessalonians 2:19 Because you are our glorying, even as we also are yours 2 Corinthians 1:14, i.e. that I may be able to rejoice in you greatly. How do you say, That your glorying may abound? I may glory the more when you make progress.
Through my presence with you again. What then! Did he come to them? Search ye whether he came.