Lord Krishna warns that the root cause for all sin and evil arises from desire and anger and that these have to be kept under control. All beings are bound by their innate tendencies, the gunas. The attraction and dislike that an individual feels towards worldly objects is natural. Even the wise act according to the tendencies of their nature, but they are aware that the gunas cause these feelings of like and dislike.
The tendency to commit evil is overcome by having the senses under control and with a will that is not subordinate to likes and dislikes. Desire and anger are man’s enemies deluding him from the awareness of the Self, just as smoke hides fire or dust the mirror.
In a discourse, Aasuri Sri Madhavachariar pointed out that Rama’s killing of Subhahu and sparing of Maricha’s life illustrate a profound truth regarding the twin evils of anger and desire in the lives of individuals. Subhahu represents anger that has to be nipped in the bud and Lord Rama killed him straightaway. Though anger has to be kept in check, one can become angry for righteous reasons, say the Sastras. For instance, one can become angry against someone censuring the Supreme Brahman or the Acharya (who instructs and inspires in us the awareness of the Brahman). When disciples stray from the path of dharma, a preceptor gets angry and chastises them just as a father would reprimand the erring son.
Maricha, the demon, stands for desire and Rama delayed his killing to show that desire should not be destroyed indiscriminately. Desire for worldly objects distracts one from the path of salvation. But of what avail is a man’s life if there is no desire for salvation and for God? When one shows love for God, it matures into bhakti. Parental love, friendship and marital love, etc., are all forms of desire. When desire turns evil, and is directed towards wrong objects, it has to be curbed. In Maricha’s case, he supported the evil intentions of Ravana, and became the cause for Sita’s abduction. His act caused danger to Sita and, therefore, Rama did not spare him.
The Lord is strict about dharma and says He will not forgive those who do not uphold it.