This ceremony is a part of monastic discipline, and a custom, established by the Buddha which supports skilful parting of the ways. When we spend time in each other’s company, even with the best of intentions, we can say or do things that cause difficulty or pain for others. The Buddha recognized this and established this simple exchange whereby, when such a parting is about to occur, the juniors begin by requesting the forgiveness of the elder for anything they might have done which has brought on hurt of any kind. The elder then responds by asking, in return, for forgiveness for any action that similarly might have caused pain.