Compassion and Impermanence

Is compassion something we need to cultivate actively or does it simply emerge if we get out of the way? Akong Tulku Rinpoche says that it is natural and spontaneous but that it needs to be awakened. He also suggests that a proper reflection on impermanence will help in this regard.

In his marvelous book on Tibetan therapy, Taming the Tiger, Rinpoche writes:

While there is nothing wrong with enjoying our lives, we should never forget that everything is impermanent, including ourselves, and that our time is far too precious to waste. Although we can be sure that death will come, the time and place of its occurrence is very uncertain. Since we can be sure that at the time of death we would certainly give everything we own for just one more day of life, we should not put off for one moment the awakening of compassion. For when we have to leave all else behind, it is the good we have done that will give us the greatest peace and comfort.
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Remembering that we are going to die does not suggest that we should live in fear and terror of death, for to become hopeless and afraid would be of no use, and would prevent us from enjoying life. Rather we should be inspired by the inevitability of death to make the most of each precious moment in order to cultivate our inner strength, loving-kindness and compassion. Then, no matter when we are to die, we will have done our best to make of our lives something valuable and useful both for
ourselves and for others.