The person that wrote that almost gets it but there is something missing in their understanding.
'The Plan is about God’s Glory and our humble service of Him. In fact, just being able to serve Him is wonderful in and of itself.'
Close but not quite. Yes the plan is about God's glory and our service for Him. Saying that being able to serve God is wonderful is a huge understatement. Serving God is so far beyond wonderful. Paul rejoices in the love of Christ all the time regardless of the physical circumstances that he may find himself. In loving God and loving Christ, we receive the love of Christ that fills us so that there is no room for anything else inside of us. Paul rejoices in the blissful worship of Christ, that is to dwell in Christ and abide in Him, that is what it is all about and Paul understood this very well. When Paul undergoes persecutions and trials, those around him witness that he is unbreakable through those trials because he abides in Christ. People are amazed that Paul always remains faithful and filled with love and rejoices even in what should result in suffering. This is as great of a miracle as any of the amazing healings and miracles performed by Jesus. These people who witness Paul acting in this way, witnessing this miracle of faith are drawn to Christ because they see the effect that Christ has on a person.