Suffering arises from thoughts that are directed towards the past, present, and future. When we think about times in the past, we again feel situations that we went through and the sadness that then overcomes us is a delusion. It is impossible to alter the past, so pondering mistakes we made or misfortunes we once experienced causes us to suffer more than had already been the case and is useless. Thoughts about the future are mostly pessimistic and therefore also cause us to suffer. They tend to make us much more sorrowful than those we have about the past. We do not suffer when we focus our attention on the present moment, which is what we do when we meditate. Nothing new is created through meditation, rather, we rest in the experience of our mind’s true nature when we meditate.

-- Bokar Rinpoche