So when we talk about having a life-force within us, this life-force is basically referring to one's physical body and one's mind being joined together. When this joining of these two aggregates is broken, this is what is known as 'death', or the separation of the life-force.
When this occurs, one's physical form remains and is buried or whatever, and the aggregate of consciousness goes on to one's future existence.
Now death is something which is definitely going to happen to all of us, but the time of our death is something which is uncertain. If it were certain then some people might even mark it on the calendar and postpone practice until a later date. But of course this is never the case, as any one of us could pass away at any time. Therefore, we should really strive to engage in the practice of the Dharma while we still have this rare and precious chance.
Denma Locho Rinpoche
If we understand that by its nature, cyclic existence is unsatisfactory, we will have a deep aversion to it. If we do not have a deep aversion to it, we will not be determined to be free, and therefore will not be able to destroy our self-grasping ignorance, which is the root of cyclic existence. In that case, we will not be able to attain liberation.
However, when we deeply feel the extent to which we suffer in cyclic existence, we will automatically want to abandon the true origin of suffering, attain the true cessation, and meditate on the true path. Having realized true suffering, we will easily realize the other three of the four noble truths.
Thus it is said: suffering is to be known. The origin is to be abandoned. The cessation is to be attained. The path is to be practiced.
The determination to be free is the wish for ourselves to be free of cyclic existence. When we wish others to be free, that is compassion.
Geshe Jampa Tegchok
In a worldly way, we already consider our lives to be precious and strive to preserve our own existence. The trouble is that we generally identify ourselves by, and with, its least valuable aspects. The ordinary sense of ‘preciousness’ consists of trying to protect the body from getting old, sick, cold, or hungry.
If we limit ourselves to these pre-occupations, without seeing beyond them, we are failing to make the most of our far greater opportunities – our potential is being wasted.
An effortless compassion can arise for all beings who have not realized their true nature. So limitless is it that if tears could express it, you would cry without end. Not only compassion, but tremendous skillful means can be born when you realize the nature of mind. Also you are naturally liberated from all suffering and fear, such as the fear of birth, death and the intermediate state.
Then if you were to speak of the joy and bliss that arise from this realization, it is said by the buddhas that if you were to gather all the glory, enjoyment, pleasure and happiness of the world and put it all together, it would not approach one tiny fraction of the bliss that you experience upon realizing the nature of mind.
Nyoshul Khen Rinpoche