"Paul and Timothy, bondservants of Jesus Christ, to all the saints in Christ Jesus who are at Philippi, with the bishops and deacons: grace to you and peace from God our Father and the Lord Jesus Christ. I thank my God upon every remembrance of you, always in every prayer of mine making request for you all with joy, for your fellowship in the gospel from the first day until now, being confident of this very thing, that He who has begun a good work in you will complete in until the day of Jesus Christ; just as it is right for me to think this of you all, because I have you in my heart, in as much as both in my chains and in the defense and confirmation of the gospel, you all are partakers with me of grace. For god is my witness, how greatly I long for you all with the affection of Jesus Christ. And this I pray, that your love may abound still more and more in knowledge and all discernment, that you may approve the things that are excellent, that you may be sincere and without offense till the day of Christ, being filled with the fruits of righteousness which are by Jesus Christ, to the glory and praise of God." -Philippians 1:1-11 (NKJV)
Every time Paul prays for the Philippians, it's a prayer of thanks and joy. His gratefulness is because of their partnership in the gospel that remained throughout the years. Do you see? Steadfast love produces joy. The Philippians loved Paul well by partnering with him in the gospel over time. They didn't pitch in just for a season, but they remained by his side for the long haul. We are called to this type of partnership. When you look at the relationships that have the greatest impact on others, it is the ones in which people love each other faithfully in all seasons of life.