But have you ever wondered, why this pain first of all occurs in our body? Pain in your body is just the "Effect" in "Cause & Effect" cycle of this nature. As Pain is the "Effect" then what is the "Cause" of this pain.
As per Bhagwat Gita, "Cause and Effect" of this material world are due to 3 qualities of Nature only & those are "Sattva, Rajas & Tamas". Due to these three qualities of Nature only our body is born. Due to individual being doing Karmas (Good & Bad), one enjoys Joy & also suffer Pain in this life. In effect Nature is of dual characteristics & "Good & Bad", "Joy & Pain" etc. are both due to dual characteristics of this nature. The living entity in material nature enjoys the three modes of nature & it is due to his association with that material nature only that he meets with good and evil consequences in his/her lifetime. Now here below are the Bhagwat Gita verses which details about the three modes of nature and how an individual gets involved with these three modes of nature & enjoys happiness & suffers pain. Basically it explains Cause and Effect in Nature.
In Bhagwat Gita Lord Sri Krishna says to Arjuna :
"Material nature consists of three modes—Goodness, Passion and Ignorance (Sattva, Rajas & Tamas). When an individual living entity comes in contact with nature, he becomes conditioned by these three modes." - (Bhagwat Gita: Chapter Fourteen verse 5)
"The mode of Goodness, being purer than the other two, is illuminating, and it frees one from all sinful reactions. Those situated in that mode become conditioned by a sense of happiness and knowledge." - (Bhagwat Gita: Chapter Fourteen verse 6)
"The mode of Passion is born of unlimited desires and longings, and because of this, the embodied living entity is bound to material fruit producing actions." - (Bhagwat Gita: Chapter Fourteen verse 7)
"Know that the mode of Darkness, born of ignorance, is the delusion of all embodied living entities. The results of this mode are madness, indolence and sleep, which bind the conditioned soul." - (Bhagwat Gita: Chapter Fourteen verse 8)
"The mode of Goodness conditions one to happiness; Passion conditions one to fruit producing action & pain; and Ignorance, covering one’s knowledge, binds one to madness." - (Bhagwat Gita: Chapter Fourteen verse 9)
Now you have to see that in which of the above said modes of nature you are established. If you are doing good Karmas, helping others, living a pure life, having devotion to God, doing acts of sacrifice, charity etc. then you are living a Sattvic life & it frees one from all sinful reactions & gives a life of happiness.
If you live a passionate (Rajasic) life, addicted to sensuous pleasures of life then it shall give pain in life (physical & mental later on). Though sensuous pleasures look good at the time of it's enjoyment but ultimately it's consequence is pain only & it leads one to all painful reactions .
That happiness which is derived from contact of the senses with their objects and which appears like nectar at first but gives pain at the end is said to be of the nature of passion. - (Bhagwat Gita: Chapter Eighteen verse 38)
If you lead a lazy life, enjoys happiness in sleep, indolence etc. & are egoistic, avoid doing your duty; then you are living in delusion. All this arises of the nature of ignorance & in this case you are leading a Tamasic life. Such a life gives pain only always & lead one to utter delusion before & after.
So its all, what type of life you live & what type of Karmas you do. Sattvic life shall lead you to happiness only while Rajasic life shall lead you to Pain & Suffering while Tamasic life shall lead you to utter delusion & shall ruin your life. Choice is yours, which type of life you want to live.
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