What does Romans 12:15 mean?

Of all people, Christians should be masters of empathy, according to Paul. He commands those who are in Christ to be submissive to each other even in our emotions. Nothing communicates sincere love and concern for another person more powerfully than recognizing and joining in their highs and lows. We show love by empathizing with their seasons of celebration and allowing ourselves to feel broken with them in their seasons of heartache.

Jesus Himself powerfully modeled this in John 11:33–35. He was deeply moved and wept with Mary and the others after Lazarus had died. Jesus knew He would raise Lazarus from dead, but that did not keep Him from joining in the sadness of those experiencing the loss.

Saved believers have been shown great grace by God (Romans 3:23–24), who experienced our temptations and suffering (Hebrews 4:15–16). Just as Christians, who have been shown great mercy, ought to be merciful to others (Romans 11:30–31; Ephesians 4:32), so too should they reflect God's empathy through compassion for others.