Sovietnik wrote:How much can meditation (I'm talking mostly about vipassana) change one's personality? Can it turn a hateful, easily irritable and lazy/impatient person into someone much more psychologically healthy?
Yes. Hate, irritation, laziness, and impatience are unpleasant experiences in themselves and lead to unpleasant experiences and are influenced by choices. Greater insight into the process by which choices influence states of mind and pleasantness of experience leads to greater skill in making choices, which reduces the arising of feelings of hate, irritation, laziness, and impatience.
This concept of self harm through ignorance is touched on in MN 75
MN 75: Magandiya Sutta wrote:Magandiya, suppose that there was a leper covered with sores and infections, devoured by worms, picking the scabs off the openings of his wounds with his nails, cauterizing his body over a pit of glowing embers. His friends, companions, & relatives would take him to a doctor. The doctor would concoct medicine for him, and thanks to the medicine he would be cured of his leprosy: well & happy, free, master of himself, going wherever he liked. Then suppose two strong men, having grabbed him with their arms, were to drag him to a pit of glowing embers. What do you think? Wouldn't he twist his body this way & that?"
Abandoning these things is also specifically described as one of the first skills developed in meditation practice in DN 2
. Hate and irritation are matters of ill will. Laziness is a matter of sloth. Impatience is a matter of restlessness and anxiety.
DN 2: Samaññaphala Sutta wrote:"Endowed with this noble aggregate of virtue, this noble restraint over the sense faculties, this noble mindfulness and alertness, and this noble contentment, he seeks out a secluded dwelling: a forest, the shade of a tree, a mountain, a glen, a hillside cave, a charnel ground, a jungle grove, the open air, a heap of straw. After his meal, returning from his alms round, he sits down, crosses his legs, holds his body erect, and brings mindfulness to the fore.
"Abandoning covetousness with regard to the world, he dwells with an awareness devoid of covetousness. He cleanses his mind of covetousness. Abandoning ill will and anger, he dwells with an awareness devoid of ill will, sympathetic with the welfare of all living beings. He cleanses his mind of ill will and anger. Abandoning sloth and drowsiness, he dwells with an awareness devoid of sloth and drowsiness, mindful, alert, percipient of light. He cleanses his mind of sloth and drowsiness. Abandoning restlessness and anxiety, he dwells undisturbed, his mind inwardly stilled. He cleanses his mind of restlessness and anxiety. Abandoning uncertainty, he dwells having crossed over uncertainty, with no perplexity with regard to skillful mental qualities. He cleanses his mind of uncertainty.