The Buddha encouraged us to reflect on the fact that death could come at any time. This sobering reflection, when used in the right way, brings sharpness and clarity as to what is important in our lives
Reflecting on asubha (the non-beautiful) aspects of the body we can find greater peace and acceptance with things as they are. Through this understanding, the mind is released from desire and aversion
This practice, one of the Four Protective Meditations, leads us to directly understand the true nature of the body. Through this understanding, the mind is released from desire and aversion and we can accept this body as part of nature, rather than "me" and "mine".