Over and over again, I have emphasized the urgency of a careful practice of the uncertainty of human life, and some of my students also promised with great assurance to do so in front of me. They did think they should listen to their teacher at that moment, but their promises cannot be kept much longer, since distracting thoughts always occur to them simultaneously which quickly makes the promises unrecognizable. In this way they have lost themselves in the end. None of us can ever be sure that we will still be alive tomorrow. Thus no matter how long a life we are endowed with in this life, we ought to focus our reflection upon the next life and interrogate ourselves where we should go then.
Tenzin Zangpo Rinpoche 丹真絨布仁波切