A Rishi is a title given to someone who has attained enlightenment. They are credited with writing the original Vedic hymns. However, from the post-Vedic tradition of Hinduism to the twenty-first century, they are often regarded as “great yogis” or “sages” who have attained enlightenment and realized the eternal truth after years of intense austerity.
The Jaiminiya Brahmana and Brihadaranyaka Upanishads contain some of the earliest mentions of Rishis. However, in Hinduism, Rishis are the people who have already conquered their human emotions, such as anger, greed, attachment, ego, jealousy, and so on, and can see the supreme reality beyond the materialistic world.
One of the greatest Rishis of all time, Vishwamitra, who wrote the famous Gayatri Mantra, was a Kshatriya (or military caste), whereas Valmiki, the original author of Ramayana, came from a hunter tribe (a lower caste in a sense).
Maharishi, also known as “Maharsi”, is an honorary title bestowed to a Rishi upon attaining the highest level of wisdom and asceticism.
According to Hindu beliefs, they are born very rarely, often once or twice every couple of centuries.
The term Muni is derived from the Sanskrit word “mounam”, which means “to remain silent“. Therefore, a Muni is someone who can control and silence their illogical thoughts.
Munis are a type of philosopher, thinker, and introverted person who usually lives in retirement, meditates and adheres to the vow of noble silence (or, Mauna). They typically live alone and normally do not impart knowledge to others, but stay busy in their own quest of finding the self.
The word “Sadhu” literally translates to “anything that is good” in Sanskrit. Therefore a sadhu is someone who is very good in nature. However, it is a very broad term to interpret their characteristics upon. Sadhu is also used to call holy men who are on the path of seeking enlightenment.
The majority of sadhus are men, but there are a few sects of female sadhus known as Sadhvis.
According to Hindu beliefs, a person is called a Sanyasi when he renounces the world by performing his own funeral to live a meditative life. They do this to live a life without the toxicity of having money, power, prestige, and any kind of family bonding – basically by detaching themselves from society.
Sanyasi believes that the world is an illusion and that all of the joys and pleasures that come from the material world are toxic and never last.