Skanda Shasti is an occasion, considered very special for worshipping Lord Skanda or Muruga.
Shasti is the sixth Thithi or the lunar day, and here, it refers to the one falling in Shukla Paksha, the waxing phase of the Moon. Such a Shasti day that comes in the month of Ashwin (October–November) is observed as Skanda Shasti. It was on that day that Muruga (after fighting a heroic battle with the Asura forces) put an end to the atrocities of the mighty demon Soorapadma. The occasion of Skanda Shasti, the Shasti day meant for Skanda worship, involves great celebrations, when devotees observe Vrats like fasting, perform other austerities, visit his temples in large numbers and offer prayers to him.
There are fascinating legends about Soora, as Soorapadma is often called as and about SooraSamhara, his destruction.
According to a mythological account, it was none other than king Daksha who took birth as Soorapadma in his subsequent birth.
Once, the divine mother was born as Daksha’s daughter and chose Shiva as her consort, much against the wishes of her father. Daksha bore a severe grouse against the Lord for marrying his daughter against his will, and this led to some regrettable incidents. These ended with his daughter Dakshayani immolating herself in the sacrificial fire of the Yagya that her father himself had organized and Shiva, out of terrible rage, annihilating Daksha there itself, though reviving him later with a goat’s head.
This Dakshayani came back as Goddess Parvati, got married to Shiva again and their son was Lord Muruga. Thus Muruga’s relationship with Soorapadma happens to be the same as between a grandson and a grandfather.
Soorasamharam is the biggest and the most significant celebration that takes place in the Muruga temples on the Skanda Shasti day. This commemorates the final victory of the Lord over the Asura army led by Soorapadma. Though the term ‘SooraSamhara’ literally means the ‘slaying of Soorapadma,’ what happened then was very different and exciting. Muruga didn’t kill Soora, instead only turned him into a peacock and rooster, making the peacock his mount and keeping the rooster in his flag. Thus, what Muruga did at the end of the war was not annihilation, as it usually happens when the Gods fight the demons in a bloody battle; but it was only the transformation of Soorapadma. The Lord thus reformed evil, turned that into good and kept that always close to him.
The grandfather-grandson relationship that existed between Soora and Muruga can also be cited as one of the reasons, for this remarkable turn of events and the end to their conflict.