Think of unity as like being in a marching band. Each person has an instrument to play and steps to march. If even one person is out of step, even if they’re playing all the right notes, the entire marching band can go off, and their routine may be ruined (Bob Deffinbaugh, “36. Pleasing Others and Praising God (Romans 15:1–13),” Bible.org, August 18, 2004, https://bible.org/seriespage/36-pleasing-others-and-praising-god-romans-151-13).