At this point in the book of Romans, Paul transitions his teaching about being made right with God (justification) to bearing fruit for God (sanctification). What he wants his readers to know is that we bear fruit through the work of the Holy Spirit rather than through our human efforts of obedience.
What a difficult concept for us to accept! From the time sin began, mankind has been trying to earn his way back into God’s good graces. Every passage and story of the Old Testament pointed God’s people to a Savior who would rescue them, impressing upon them that their efforts to obey would always fall short. But a Savior would come who’d pay their debt once and for all. This is the good news for us, too!
The “fruit” we bear for God—any good works, any kindness shown to others, any attempts to share Jesus’ love—is a delight to Him but is not what saves us. Our law-keeping will not do it either. Only Christ who conquered sin and death can save our souls. Out of profound gratitude, we want to obey and show love to others.