Is killing a harmful insect in your home a sin in jainism

Yes. In Jainism, ahimsa (non-violence) is the guiding principle. Killing a living being, even an insect, creates karma. So, normally, killing a harmful insect in your home is considered a violent act and should be avoided. The preferred approach is to use non-lethal means (screens, nets, repellents, careful cleanliness) to prevent harm. If there is an unavoidable threat to life (for example, a real risk to people from disease), one should minimize harm and use the least violent method available.

Different Jain traditions (Digambar and Śvetāmbar) both uphold ahimsa as central; the main difference is in certain ritual and interpretive details, but neither permits casual killing of living beings when non-violent options exist.

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