Durga, a beautiful warrior seated upon a tiger, was the first appearance of the great goddess. The circumstance of her miraculous arrival was the tyranny of the monster-demon Mahishasur, who through terrific austerities had acquired invincible strength. It seemed that the joint energy of Shakti was only capable of vanquishing Mahisha, and so it was the eighteen-armed Durga who went out for the battle.

She went to the battle mounting her ferocious lion, armed with the weapons given to her by the other Gods. Durga is one of the angry and aggressive aspects of the goddess Shakti, whose role in Hindu mythology was to fight and conquer demons and also personify Shakti or female aspect of any male deity. In the battle, she fought and killed the evil Mahishasura and restored heaven to the gods. Since then the goddess is invoked for protection from the powers of evil.

During Durga Puja, which lasts for nine days, nine different forms of Devi, are worshiped over the nine days. As the ten-armed Goddess, Goddess Durga presents a radiantly beautiful form that is bewitching to behold. That special form is somehow simultaneously wrathful and benign and transmits profound spiritual teachings in an exacting manner.

The nine-day period from the new moon day to the ninth day of Ashvina is hence the most celebrated time of the year as Durga Puja. The nine different forms of Devi are worshiped over the nine days.