Is it ok to kill disease causing insects like mosquitoes, cockroaches and flies? So many flies sit on our food daily and I always have the fearing of contracting diseases. So, can I kill them with insectiside sprays? Will I collect bad karma because of this?
Yogananda as a young disciple of his guru Swami Sri Yukteswar asked this very question. Yukteswar responded:
“Man’s body is precious. It has the highest evolutionary value because of unique brain and spinal centers. These enable the advanced devotee to fully grasp and express the loftiest aspects of divinity. No lower form is so equipped. It is true that one incurs the debt of a minor sin if he is forced to kill an animal or any living thing. But the Vedas teach that wanton loss of a human body is a serious transgression against the karmic law.” (Autobiography of a Yogi by Paramhansa Yogananda 1st ed., Chapter 12).
The teachings from Yogananda are always to be practical in your idealism. This was illustrated with firsthand experience from his guru.
The teaching of ahimsa is to remove the desire to kill. Man may need to exterminate harmful creatures, but he is not compelled to feel anger or animosity toward these creatures. Most people’s transgressions against ahimsa are not at the level of overt killing but at more subtle levels. To practice ahimsa deeply we must remove harmful tendencies from our nature, including the desire to hurt another in any way — such as seeking personal benefit at another’s expense, a competitive nature with others, speaking against others, inflicting emotional harm on another, killing someone’s enthusiasm, or treating someone with disrespect.
The essential teaching is to realize our oneness with all life. When we hurt another we hurt ourselves because we are all connected. We must see ourselves also in our oneness and not injure ourselves with harmful thoughts or actions such as guilt or fear which only separate us from God. Our essential nature is good.
So you can see that ahimsa is an inner attitude which is expressed in action. Indeed when we ‘kill’ even at the level of thought there are karmic consequences as there are with overt actions. Seek to be non-violent in every aspect of your nature.