After enlightenment, Buddha started to spread his teachings about life, truth and the likes of it. He told that death and suffering are the part and parcel of life. None can avoid this truth. One has to meet one's destined end one day. Whoever has come to the world, will die one day. In the hour of grief, one must remain calm and composed so that grief doesn't overcome one. People who are wise, never complain or lament over their loss. They accept the truth and be blessed with it. So, the wisdom lies in the fact that people should not get distressed with pain, suffering and death.