Shantideva cites three benefits of pain. First it is valuable because through sorrow, pride is driven out. No matter how arrogant and condescending we’ve been, great suffering can humble us. The pain of a serious illness or loss of a loved one can be transformative, softening us and making us less self-centered.
The second benefit of pain is empathy: the compassion felt for those who wander in samsara. Our personal suffering brings compassion for others in the same situation. A young woman was telling me that when her baby died, she felt a deep connection to all the other parents who had lost children. This was, as she put it, the unexpected blessing of her sorrow.
The third value of suffering is that evil is avoided and goodness seems delightful. When we practice according to Shantideva’s instructions, we can get smarter about cause and result. Based on this understanding, we’ll have less inclination to cause harm, and more desire to gather virtue and benefit others.
From No Time to Lose: A Timely Guide to the Way of the Bodhisattva, pages 172–173.