Why must we devote our lives to help others?

You mustn't allow yourselves to grow old before your time. Please live with a youthful spirit. That is what Buddhism teaches us to do and it is how life ought to be lived. If you make a commitment to work for the sake of others, you will be rejuvenated. If you devote your life to helping others, you'll stay young. The power of Nam-myoho-renge-kyo guarantees that.

For Today and Tomorrow
Daily Encouragement by Daisaku Ikeda 17/3