Yamaraja also known as Yama, Kala and Dharmaraja is the Hindu God of Death, he also known as the God of Justice, this is why he is known as Dharmaraja. He is responsible for maintaining order and harmony in the world. The Garuda Purana mentions him as the lord that directs the soul to its next state. Even though Yama is feared by living beings, he plays a vital role in rejuvenation and maintaining the balance of the world through the continuous cycle of birth and death.
Yamaraja is the son of Lord Surya and Sanjana. He is the twin brother if Yami who became the River Yamuna. He rides a black buffalo called Mahisan. He has a dark complexion and wears red robes. He is believed to be the first mortal to ever day and that is why he is known as the god of death. On Yamaraja’s death, his twin Yami could not be consoled and hence the Gods created night and day and the cycle of time began. His eyes resemble fire, his hair is flaming. The noose of rope in his left hand is used to pull the soul from the dead, and he holds a gada. He is the keeper of Naraka Loka which is the Hindu equivalent of hell. Naraka Loka is a bottomless pit of darkness where souls are trapped for eternity and unable to be reborn.
Yama along with his book keeper Chitragupta keeps count of everybody’s deeds. Legends say that the messengers of Yamaraja call the Yamadutas, who bring all beings to the court of Yamaraja after death. When a person’s span of life runs out Yamaraja sends one of his henchmen to bring the person to his abode. At times Yama personally ascends to earth to bring a person down to his abode. The soul of the dead person is then made to appear before him, and he passes judgment according to the deeds one has carried out in their life. Here Yamaraja himself weighs the virtues and the vices of the being and passes judgment, sending the virtuous to Swarga (Heaven) and the sinners to one of the Naraka (Hell). After the punishment is over, the souls are reborn as lower or higher beings as per their merits. As per the ancient Vedic texts of Hinduism, the concept of karma equates to predicting a person’s fate and their destined existence in their next life when they are reincarnated. Both karma and reincarnation are directly tied to the judgment of Yama and form the origins of the original caste system. Ref: Vedic Feed