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Significance of Vaikunta Ekadasi:

The legend says that about vaikunta Ekadasi, the Devas were unable to bear the dictatorship of a demon 'Muran', approached Shiva, who directed them to Vishnu. A battle which lasted one thousand celestial years ensued between Lord Vishnu and the demon and the Lord realized that a new weapon was needed to slay Muran.

In order to take rest and create a new weapon, Vishnu retired to a cave named for the goddess Haimavati in Bhadrikashrama. When demon Muran tried to destroy Vishnu, while he was sleeping, the female power that emerged from Vishnu burned Muran to ashes with her glance.

Vishnu, who was pleased, named the goddess 'Ekadashi' and asked her to claim a boon. Ekadashi, instead, beseeched Vishnu that people who observed a fast on that day should be absolve their sins. People, who observed a fast on that day and worshipped Ekadashi, would attain Vaikuntha.

Fasting on Vaikunda Ekadasi:

Vaikunta Ekadasi, is considered to be the most important Ekadasi in the Sri Vaishnava tradition. According to one Vishnu Purana, observing Fast (Vratam) on Vaikunta Ekadasi day confers the benefit equivalent to observing all the Ekadasis during the year.

Fasting and all night prayer dedicated to Lord Vishnu is the main observance of the Ekadasi day. It is believed that venerating Lord Vishnu on Vaikunda Ekadasi will help to free soul from cycles of rebirth and grant moksha.

Devotee fast on Ekadasi day observe whole day fast and do japa and chant Mantra for lord narayana , who observed fast on this day get liberation from the cycle of birth and death will attain Moksha.

Vishnu Puja with Tulsi leaves is highly auspicious ritual to do on Ekadasi. This is the only day Lord Vishnu give apperence along with Goddess Mahalakshmi hence follow Lakshmi Narayana vratham is an another auspicious ritual to perform on Vaikunta Ekadasi Day.

Devotees who observe Vaikunta Ekadasi fasting do not sleep on the day. They spend the whole night at Vishnu temples or by singing prayers or listening stories dedicated to Lord Vishnu.

Vaikunta Ekadasi :

Vaikunta Ekadasi is an important festival is dedicated to Lord Narayana/ Lord Vishnu. Vaikunta Ekadasi is also known as Mokshada Ekadasi. It is believed that Vaikunta Dwaram or the gate of Lord's inner Sanctam is opened on this day and the devotees who observe fast on Vaikunta Ekadasi day will get Moksha or Liberation.

Vaikuntha Ekadashi is one of the important and auspicious days for Hindus. It falls on the eleventh day of every lunar fortnight in the month of Margazhi in traditional Hindu calendar. This year Vaikunta Ekadasi is falls on December 21st 2015.

According to Padma Purana Vaikunta Ekadasi is that Bhagvan Vishnu took the form of "Ekadasi" (female energy) to kill demon Muran. This happened during the month of Margazhi. On the Powerful day of Ekadasi, whoever worships him will reach Vaikunta (heaven).

Vaikunta Ekadasi Celebration:

Vaikunta Ekadasi festival is celebrated in all Vishnu Temple. Especially Tirupati BalajiTemple, SrirangamRanganathaswamyTemple, and Bhadrachalam Sita Ramachandraswamy temple celebrates vaikunta Ekadasi festival in a great importants. The most auspicious ritual on the day in temples is the opening of the Paramapada Vasal or Vaikunta Dwaram or Soorkavasal door in Vishnu Temples. This door is only opened on the Vaikunta Ekadasi day and devotees are allowed to pass through it. Symbolically the door leads to the Vaikunta - abode of Lord Vishnu.

Celebration in Sri Ranganathaswamy Temple:

In Srirangam Ranganathaswamy Temple the Vaikunta Ekadashi celebrations last for 21 days. The deity Vishnu, in the form of Ranganatha, is decorated with an armor of diamonds called rathnaangi. The northern gate called Paramapada Vasal is opened and the deity is brought from the sanctum to the Thousand-Pillared Hall. The divine text Nalayira Divya Pradandham is recited throughout the day in the temple. Bhajans are sung by priest and devotees

Celebration in Tirumala Venkateswara Temple:

The Tirumala Venkateswara Temple does grand ceremonies and festivities during Vaikunta Ekadasi. The Vaikunta Dwaram is a special entrance encircling the sanctum. This entrance is opened only during this festival and it is believed that devotees passing through the Dwaram attain salvation. The Tirumala temple is flooded with devotees, pilgrims and dignitaries from all over India during the Vaikunta Ekadashi festival.

Celebration in Bhadrachalam Sita Ramachandraswamy Temple:

Bhadrachalam Sita Ramachandraswamy Temple, Andrapradesh is celebrated vaikunta Ekadasi in a grant manner. Teppotsavam is the major event along with Dashavatara Alankaram rituals during Vaikunta Ekadasi which is celebrated for 10 days.

During Teppotsavam, the presiding deities of Bhadrachalam Sri Sita Ramachandra swamy temple are decorated with jewelries and flower garlands and taken on Hamsa Vahanam or a boat designed like swan. Teppotsavam is a float festival or celestial cruise of the presiding deities in Godavari waters. Temple priests recite vedic hymns during Teppotsavam festival.

Mantra to Chant on Vaikunta Ekadasi:

Chanting Narayana Ashtakshari Mantra - Om Namo Narayana is highly auspicious.

Sloka to Chant on Vaikunta Ekadasi:

Sashankha chakram sakireeta Kundalam Sapeethavasthram Sarasheery Hekshanam
sahaara Vaksha Sthala Kausthubha Shriyam Namami Vishnu Shirasaa Chaturbhujam

Do's :

Clean your House before the day Vaikunta Ekadasi
Wake up early in the morning. Take bath and offer prayers to Lord Vishnu
Can perform a simple puja to Lord Vishnu at home by offering fruits and Tulsi leaves.
You can just light the lamp and prayer or meditate for few minutes ? or the normal ritual you do daily.
Visit nearby Vishnu temple and do pujas and rituals.
Complete fast or upavasam on the day is the main observance