About Shastiapthapoorthi | 60th Birthday:
The average age of a human being is 120 years old. Shastiapthapoorthi is celebrated in the person who completes his 60 years exactly in his star of birth. In fact, the year of birth of the person, the month of birth, a birth star at the time of birth, will not reappear until you are 60 years old. Therefore, Shastiapthapoorthi is celebrated that day. Therefore, this particular day is considered auspicious to celebrate Shastiapthapoorthi, regardless of Ashtami, Navami, Kari Naal, Tuesdays, Saturdays, etc. Shastiapthapoorthi is celebrated only on the day of Jenma Nakshatra (star of birth). To take into account, the year of birth, the month of birth and the star of birth would appear for the third time at 120 years.
History of Thirukadaiyur Temple:
To find out why Shastiapthapoorthi is celebrated in Thirukadaiyur, we need to know the history of the temple, that is, the Stala Puraanam of the Thirukadaiyur Temple. The name of Shiva in the temple of Thirukadaiyur is Swami Amirthakadeshwarar. In all the temples of Shiva, Lord Shiva takes the form of the Lingam called Shiva Linga Swaroopam. Tell us why Lord Shiva received the name Amirthakadeshwar. From the ocean (Paarkadal) to take the Amirdham, there was a war between Asuras and Devas. Lord Vishnu took the form of a dazzling beauty (Mohini Avataaram) and with the intention of getting the Devas to get the Amirdham, he defrauded the Asuras and brought the Amirdha Kadam. The name of the pond behind the temple of Thirukadaiyur is called Amirtha Pushkarani. Pushkarani means Thirukulam (sacred pond). Then Lord Vishnu decided to deliver the Amirtham to the Devas in this Pushkarani. This avatharam name for Lord Vishu is called Amitha Narayana Perumal. This temple is located south of Thirukadaiyur with the name of God Amirthanarayana perumal and goddess Amirthavalli.
Hence, before distributing the Amirtham, devas took bath (Snanam) and to their surprise when they returned the Amirtha kalasam was not there. This is because of the reason that Devas did not pray the first God Vinayaga (Lord Ganesha) before taking the Amirtham. So, Lord Vinayaga got angry and had stolen the Amirtha kalasam and hidden the same. Hence, this temple Vinayagar is called as Kalla Vinayagar. In Sanskrit, he is known as Chora Ganapathy. So, every deity in this temple has a name derived from the story, like Amirtha narayana perumal, Kallan Vinayagar, etc. The place where the Amirtha kadam was hidden was a Vilvavanam (vilva forest) and hence this Kshetram was popularly known Vilvaaranya Kshetram. Since this Amirdham was hidden beneath the Vilva Tree, it had become Swayambhu Moorthy (Eswaran). Since the Amirdha Kadam has become Swayambhu Moorthy Eshwar, the Swami here is known as Amirthakadeshwarar i.,e Amirtham + Kadam + Eshwarar.
Ever-16 Markandeyar:
It is believed that there is no death when consumed Amirtham. Likewise, if we offer our prayers to Amirthakadeshwarar, there would be no Yama Fear. This is the reason why Markandeyar migrated here from his native place Thondi and had settled in T. Manalmedu (0.5 km southwest of Thirukadaiyur). He had worshipped Lord Amirthakadeshwar, offered Abishegam from the Holy Ganga water to increase his life longevity since his death was fixed on the day of his completing 16 years. Accordingly, on that particular day when Markandeyar completes his 16 years, Lord Yama appeared to take his Ayul. Lord Shiva for the sake of his sincere devotee Markandeyar, took the form of Rudra – Rudra Avadaaram (Man from) and had kicked Lord Yama with his left leg and killed Yama. Since Lord Shiva Killed Kaalan (Yaman), he is popularly known as Kaala Samhara Murthy. This event of Yama Samharam is still popular in Thirukadaiyur which takes every year during the First month of the Tamil Year Chithirai (Mesha Month) during Magam star.
Why Shastiapthapoorthi at Thirukadaiyur Temple:
Markandeyar also got the boon of Ever-16 (Siranjeevi) from Lord Shiva. This is the primary reason why Shastiapthapoorthi is very famous and is being celebrated in Thirukadaiyur. Every human being is born based on the Karma palan and is being dominated by the Nine ruling planets (Navagrahas). Among the planets, Saturn (Shani) is considered as the most powerful as he fixes human birth and death, based on the Karma. Hence, he is called as Ayushkaaragan. Yamadharma raja is the younger brother of Lord Shani.
All the planets have their effect and domination on a human only when the person is alive. For example, Sukran given family & children, Sevvai gives wealth, Budhan for education etc. These are applicable only if the person is alive. Once the human dies, the power and responsibility of taking his Aathma lie with Shani Bhagawan. For completing this responsible task, Shani appoints Lord Yama for the same.
Hence, Yama takes the job of taking away life from a human on the destined date.
Since in Thirukadaiyur, Yamadharma was killed by Lord Shiva, Shani was left with no power. When the ruling planet Shani has no power, all other planets follow the same rule. Normally in all Shiva Temples, there would be a separate Sannidhi for Navagrahas. But in Thirukadaiyur temple, there is no sannidhi for Navagraha, as the same has no power.
When the same year, same month and birth star when it was during the time of birth comes for the 2nd time i.e, during the completion of 60 years, there would be some negative vibrations and unwellness. Shastiapthapoorthi is celebrated at Thirukadaiyur to overcome this hurdle and increase life longevity. Also for the married couples, the event of Thirumangalya dharanam (mangalsutra tying) is done again to increase the power of Mangalya.
Other Ayul Shanthi Parihara Homams in Thirukadaiyur Temple:
In the average age of human being, as per Sastra, he needs to overcome 4 radams (rathas in Sanskrit means Korai teeth like lion teeth). The first ratha at the beginning of 60 years, next at the completion of 60 years, 3rd one at the beginning of 70 years and the 4th radha at the completion of 75 years). Hence, the following 4 Shanthi homams are performed for the 4 rathas.
1) Ugra Ratha Shanthi is performed at the beginning of 60 years
2) Rudra Ratha shanthi is Rudra Abhishekam, Shatiapthapoorthi is performed after completion of 60 years.
3) Bheema Ratha Shanthi is performed at the begging of 70 years
4) Vijaya Ratha Shanthi is performed at the completion of 74 years.
5) Ayul Mritunjeya Homam is For life longevity and to get rid of negative impacts resulting in the overall well-being of the person.