The Buddha explained to us that our fortunes are dependent on karma. This is simply the law of cause and effect — our actions have consequences.
When we practice insight meditation we take advantage of this law as it relates to the habit forming nature of the mind. In other words, whenever we act, we are not only setting in motion physical causes and effects, we are also conditioning the mind in one direction or another. It is this conditioning that is central to the Buddha’s teaching.
If we condition the mind appropriately, we can eventually create routines around positive and wholesome actions. The most significant of these is the habit of mindfulness because it can be practiced all day long.
However, in order to get to the point where mindfulness preoccupies the mind on a moment-to-moment basis, we need to create training routines. These routines include our daily practice and our regular retreats.
If we can embed these routines into our lifestyle, their effect will eventually overpower any negative karma that we have unfortunately accumulated. Our habits will then slowly gravitate in favor of actions that lead to happiness and we can begin to leave suffering behind.