When people grow up and become adults, they take responsibility for themselves. They start paying their own bills, making their own food, and handling all the affairs of their own life.
Then one day, they reach a new level of maturity. That is the day they start taking care of other people. This could include caring for a newborn or an aging parent. There is this shift from a self-centered focus to an others-centered one.
The other day I watched someone and saw an even higher level of maturity. That is when someone starts caring for other people without being asked and without obligation. This person saw a need and stepped up to help despite them not being connected in any way.
What is true of physical maturity is also true for spiritual maturity. The closer someone gets to Jesus, the more they are willing to step up and serve others without being asked, even when they have nothing to gain from it.