yada kadacij jivatma
nana-yonisv aniso ’yam
paurusim gatim avrajet
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
While rotating in the cycle of birth and death again and again in different species because of his own fruitive activities, the dependent living entity, by good fortune, may happen to become a human being. This human birth is very rarely obtained.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The Supreme Personality of Godhead is fully independent. Thus it is not always a fact that a living being’s loss of all opulence is a sign of the Supreme Lord’s mercy upon him. The Lord can act any way He likes. He may take away one’s opulence, or He may not. There are varieties of forms of life, and the Lord treats them according to the circumstances, as He chooses. Generally it is to be understood that the human form of life is one of great responsibility.
purusah prakrti-stho hi
bhunkte prakrtijan gunan
karanam guna-sango ’sya
“The living entity in material nature follows the ways of life, enjoying the three modes of nature. This is due to his association with that material nature. Thus he meets with good and evil amongst various species.” (Bg. 13.22) After thus rotating through many, many forms of life in the cycle of birth and death, the living being gets a chance for a human form. Therefore every human being, especially one belonging to a civilized nation or culture, must be extremely responsible in his activities. He should not risk degradation in the next life. Because the body will change (tatha dehantara-praptir), we should be extremely careful. To see to the proper use of life is the purpose of Krsna consciousness. The foolish living entity declares freedom from all control, but factually he is not free; he is fully under the control of material nature. He must therefore be most careful and responsible in the activities of his life.