Romans 15:27
It hath pleased them verily; and their debtors they are. For if the Gentiles have been made partakers of their spiritual things, their duty is also to minister unto them in carnal things. It hath pleased them verily; and their debtors they are. For if the Gentiles have been made partakers of their spiritual things, their duty is also to minister unto them in carnal things.
Gentile believers who had been made partakers of spiritual things through Jewish believers were debtors to them, and their duty was to minister to them in material things in return. The collection that Paul carried to Jerusalem and Judea for the poor saints there was the fitting return and expression of that duty. Even the poor Philippians joined that collection readily, giving from their limited means to help churches more needy than their own. Those gifts expressed the Gentile converts' love and sympathy for their Jewish brethren and their desire for harmony.
They fulfilled the commitment to remember the poor. Paul hoped this service would strengthen unity between Jewish and Gentile Christians. He gathered the gift to open a way to preach the truth in Jerusalem, where many did not believe that Jesus had risen and was the living Son of God.
After delivering this gift as the fruit of the Gentiles' faith, he planned to travel to Spain by way of Rome. The same principle means that those who receive spiritual blessings should share material goods with those who minister spiritual things, supporting systematic giving and helping those in need. The service the verse calls for requires sanctified brain power and sanctified talent of speech, and only when both are sanctified is a person fitted for it.