Introduction
Markandeya is a sage, the son of the sage Mrikandu, fated at birth to live only sixteen years. His survival, through unwavering devotion to Shiva and Shiva's direct intervention against Yama, made him a byword for the power of devotion to overcome even death, and he is honoured with permanent youth.
This article follows the Puranic tradition. Where a detail differs between texts, the article says so.
The short life
Markandeya's father Mrikandu was told he could have either a foolish son who would live long, or a wise and virtuous son fated to die at sixteen. He chose the second, and Markandeya grew into a devoted worshipper of Shiva, aware from childhood of his own approaching death.
Yama's arrival
As his sixteenth year ended, Markandeya was worshipping a Shiva linga when Yama, the god of death, arrived personally to claim him. Markandeya clung to the linga in his devotion and refused to let go even as Yama's noose approached.
Shiva's intervention
Shiva emerged from the linga in fury and struck down Yama himself to protect his devotee, in the form celebrated as Kalantaka, "ender of Time (Death)", or Kalasamhara Murti. Yama was later restored to his office, but Markandeya's life was granted an exception: he would remain sixteen forever, never ageing or dying.
Later role
In several Puranas, Markandeya, as an immortal, becomes a narrator of cosmological and mythological teaching to later generations, and the Markandeya Purana, one of the eighteen major Puranas, is named for and framed as taught by him.
Worship
The story is commemorated in Shaiva worship, particularly associated with longevity and the overcoming of untimely death, and is recited especially by those observing vows for a long life or the health of a family member.