Bhagavad Gita

ಕಾಮ ಏಷ ಕ್ರೋಧ ಏಷ ರಜೋಗುಣಸಮುದ್ಭವಃ।
ಮಹಾಶನೋ ಮಹಾಪಾಪ್ಮಾ ವಿದ್ಧ್ಯೇನಮಿಹ ವೈರಿಣಮ್॥೩೭॥
kāma eṣa krodha eṣa rajoguṇasamudbhavaḥ|
mahāśano mahāpāpmā viddhyenamiha vairiṇam||37||

Gist of the sloka:
Bhagawan spoke: The one which provokes sin is Kama [all desires whose controller is daemon Kalanemi]. The version of this is anger through Rajasic birth. This is like an uncontrolled hunger with no end. The greatest of Hell is its birthplace. For a seeker, this is obstruction in his path.
For everything the root cause is desire. Some desire is always persisting in our minds. We can, by committing wrong actions can the desire be fulfilled? is the temptation which will bother us. The force which makes us do it is the daemon Kalanemi. If he resides in us, then he will ensure we do his bidding.
There are primarily two factors which causes sinful actions. Desire and anger. One who has intense desire will have intense anger and with that anger what all the actions he undertakes is impossible to say. Maybe after realizing what he has done, he might regret. The root cause for anger is desire. Without desire, one cannot get anger. Behind anger is the intense desire.
The Rajasic qualities in the man is like hunger without end. A good example of this would like a unemployed person who is looking for a job for a long time. His aspiration would be to get some job so that his basic needs are fulfilled. Through grace of Lord, he obtains a position with sufficient salary to fulfill his needs. Over a period of time, he sees others getting more money and his desires now increase making him greedy for higher salaries and positions.
Even after he gets it, his desires only increase making him even more greedy. His original intention is long forgotten. He will never have satisfaction with his salary or position or the needs he has already fulfilled, his basic needs long back.
If we continue to tolerate and encourage desires, the wrong actions become more and more intense and leads us to Hell. It will make us do unwanted and wrong actions [thoughts and beliefs]; including killing of a knowledgeable saint. This is the dark warning about desire that the scriptures give us. We just have to open the newspaper today to see examples of it.
Therefore, one should be always alert for such events. Controlling the desire, one should be satisfied with what Lord gives, as blessings. One should prevent such thoughts from forming itself and if already existing should drive them out. Live for righteousness and for that makes you a better persona and elevates you.