Somewhere in The Tibetan Book of Living and Dying it says (loosely) that the purpose of life is to prepare for death. A somewhat morbid statement, think about how profound a message it actually is.
For most of us, we spend our days running around doing, doing, doing. All the while creating more attachment not only to those material things around us, but also to our identities. As a result, we tend to move further and further away from conscious awareness of our true eternal nature.
As I’m sure I don’t have to remind you, in death, no one is taking anything with them. That said, meditation on death not only helps a person to prepare for the transitory (non-attached) nature of this inevitable act, but contemplation itself helps one to connect to the positive purpose of this life.
As much as each one of us would like to block out the fact that at some point our bodies will cease to exist (at least on the physical plane), the sooner a person begins to meditate on the meaning of death, the sooner one begins to live life.
Checkout this recent Hindustan Times post based on an excerpt from the Dalai Lama’s book, Becoming Enlightened. According to the Dalai Lama, meditation on death leads to contemplation, which in turn, places one on a path to positive purpose.
To make us mindful of death, the Buddha taught meditation on death. If you are mindful of death, you will be drawn into thinking of many things, particularly whether there is life after death. Even if you suspect that there is, you will take interest in the quality of that life — what it might be like.
This will lead you to think about Karma, the cause and effect of action, thereby drawing you away from choosing activities of harmful nature and encouraging you to engage in activities that are beneficial. This itself will lend your life a positive purpose.
If you try to avoid even the mention of death, then on the day when death comes, you may be frightened. However, if you contemplate the fact that death happens naturally to all living beings, this can make a big difference. When you become familiar with death, you can make preparations for dying, and decide what you should do with your mind at that time. On that day your preparation will have its effect; you will think “Ah, death has come,” and you will act as you had planned, free from fright.
Read more on using meditation to face the challenge of death here.