Here is a summary of Srila Prabhupad’s lecture : SB 5.5.1, Bombay 1977
Lord Rsabhadeva told His sons: My dear boys, of all the living entities who have accepted material bodies in this world, one who has been awarded this human form should not work hard day and night simply for sense gratification, which is available even for dogs and hogs that eat stool. One should engage in penance and austerity to attain the divine position of devotional service. By such activity, one’s heart is purified, and when one attains this position, he attains eternal, blissful life, which is transcendental to material happiness and which continues forever.
Here we can see the duty of a father. A father’s job is to instruct his children on the duty of life so that they may not live like a hog working day and night for stool and sex. Human life is meant for tapasaya. In this material world, everyone is bound by the stringent laws of maya. One cannot violate the laws of maya. One can understand this principle from fire. It does not matter whether you are an innocent child or a mature adult, if you place you hand in fire, you will be burnt. Fire will burn anyone.
Every human must understand that they are not the body and that there will be a change of body after death. Learning the purpose of life from Shastra is the way not to misuse our human birth. But no one is interested in this topic of next birth. The first instruction from Lord Krishna in Bhagavad Gita is – You are Eternal.
Human birth is meant for one to undergo austerity and renunciation. Everyone should aim to be a brahmana and following them are the Kshatriyas, Vaishyas and Sudras. It’s a great science. We must be very careful not to be carried away by the waves of material nature.
“Why am I dying?” – this is an intelligent question that one must ask. But we are ignoring this vital question and people in general have adopted a lifestyle which will not lead to mukti. We must realize ourselves and attain our original form. Understand your true business in life by following the process of bhakti. Krishna recommends, “Always think of me”. If you always think of Krishna, you become a devotee. Everyone is a part and parcel of Krishna, eternally His servant. But when they want to enjoy without Krishna, then they become bound. So, be a bhakta and get out of this material world.