We cannot learn real patience and tolerance from a guru or a friend. They can be practiced only when we come in contact with someone who creates unpleasant experiences. According to Shantideva, enemies are really good for us as we can learn a lot from them and build our inner strength.
Dalai LamaThere is no denying that consideration of others is worthwhile and that our happiness is inextricably bound up with the happiness of others. There is no denying that if society suffers, we ourselves suffer, and the more our hearts and minds are afflicted with ill-will, the more miserable we become. We can reject religion, ideology, received wisdom, but we cannot escape the need for love and compassion.
Dalai LamaToo much of a self-centered attitude creates mistrust and suspicion in others, which can in turn lead to fear. But if you have more of an open mind, and you cultivate a sense of concern for others' well-being, then, no matter what others' attitudes are, you can keep your inner peace.
Dalai Lama