The deepest insight of the Buddha is his insight into what we really are. We think of ourselves as static and unchanging, a something or a someone. But in reality we are a dynamic process of change. Every second millions of red blood cells in us die, and an equal number are born. Every molecule in us comes from the earth, the water, the sunlight, and the carbon of ancient stars. We are the net result of our genetic inheritance, the parenting we received, and every kind or unkind interaction we have had with others. At the level of intention, we are the tendencies we have created from our past actions and words: how we act today tends to perpetuate itself into how act tomorrow (karma-vipaka, the fruits of our actions).
In reality we are a patterned flow of change, a cross-section in time of a perpetually unfolding process, composed entirely of factors that are not us, but which we have come to identify with, to think of as I or me or mine. The Buddha taught that this identification with a process that is really selfless is the source of all our sorrow.
In reality, this is the same insight as the insight of impermanence I wrote about last time. If we, like everything and everyone else, are changing from moment to moment, then what are we are really? We are a life process.
If we can see this deeply enough, what sense does it make for one selfless life process to hold onto hurt and anger at the words or actions of another life process? That other person is also the cumulative result of the molecules of the universe, their genetics, their life experiences. They have been forged by these forces in the same way that we have been, in the same way that a storm is the result of atmospheric forces of immense size and complexity.
We may not like the results of the storm we encounter, especially if it has been very destructive. But does it make sense to hold a grudge against it? Does it even make sense to forgive a storm?