The Nalayira (4000 in tamil) Divya Prabandham is a collection of 4,000 verses composed before 8th century AD, by the 12 Azhvars (the term azhvar means "the one who is immersed in"). They are so called because they were immersed in their devotion and love to their Lord, Vishnu.
It was the scholar-saint Nathamuni who, in the 10th century, retrieved and compiled this divine collection and numerous commentries have been written by various poorvacharyas for this divya prabandham and it is a life time exercise to read and the understand the inner meanings of the bakthi laden pasurams.
The Prabandha sings the praise of Narayana (or Vishnu) and his many forms. The Alvars sung these songs at various sacred shrines. These shrines are known as the Divya Desams.
About 12 Alwars:
The AzhwArs are reported to be incarnations of NithasUris of Sri Vaikuntam, namely, the weapons, the Vanamaali, the GarudA, and all. They lived like human beings and burst out bhakti laden great works for the sake of humanity. The works of Alwars stood mysteriously a replica of the Vedas themselves and therefore came to be known as Dravida Veda. In fact, there is a view that even the great Rishis are no match to the greatness of the Alwars because these Rishis got their ‘jnAnam‘ ( wisdom) as a result of their own actions of ’spiritual merit’ (Punyam) whereas the wisdom of the Alwars was the direct result of the Lord’s divine grace and therefore called ‘ Divyam’. It is because of this that the works of Alwars is called ‘ Divya Prabandham’ are 4000 poems (pAsurams).
These Alwars are 12 in Number and out of which one is Sri Andal, who is a woman. These Alwars were born in various parts of our country but they were all united in a common subject, ie dedicating their lives and praising the Lord.
Poigai Alwar, Bhoodath Alwar and Pei Alwar are collectively called as "Mudhal Alwars" were found in the same period of time.
1.Poigai Alwar: an incarnation of MahAvishNu’s paanchjanyam (Divine conch, sanghu in Tamil) is also called Adhi kavi. He appeared on the lotus bud in a pond in tiruve:ka near kancheepuram.
2. Bhoodhathth Alwar: appeared in a flower called “kurukkaththi”(?) in a garden at kadalmallai port of pallava rajyam (kingdom) in mahAbalipuram (south of madras). He was an incarnation of Divine mace (called kaumOdaki) of our Lord mahAvishNu.
3. PEyazhw Alwar: as an incarnation of the sword of mahAvishNu (called nandaki), appeared in sevvalli (Red alli-lily) flower in a well of AdhikEsava perumAL koil at mylapore (in madras). (called pEyar later by people due to being crazy, mad, piththan, pEyar after the Lord and even used to roll down with ecstasy and bhakti- He even says” others look crazy to him for their being crazy after material pursuits; and sensual pleasures)
4. Thirumazhisai Alwar: an incarnation of the chakrAyudha (the Discuss of maha vishnu).He thought the Perumal as his friend and has sung Mangalasasanam on Perumal.
5.Thirumangai Alwar: who was a great king in his starting of life but later, changed his life to work for the Perumal and for his bhaktaas.
6.Thondaradippodi Alwar: who is also named as "Vipra Narayanar" led his life as the slave to the Perumal and worked for the Perumal by dedicating him with Garlands.
7.Thiruppaan Alwar: who belonged to the Paanar family, praised the Perumal through his beautiful songs and Paasurams.
8.Periyalwar: is considered as the Mother, Father for Sri Andal and Father-in-Law to Perumal has sung Mangalasasanam on Perumal.
9.Sri Andal: who is also called as "Soodikkodutha Sudar Kodi" is said to be the daughter (brought up) of Periyalwar has created "Thiruppavai" in which she considers Sriman Naryanan as her husband. She is the only lady alwar.
10.Nammalwar:an incarnation of Vishvaksena, the Chief administrator of Mahavishnu; who sat below the Tamarind tree without having any food and sleep, got wisdom and has sung Mangalasasanam on Perumal and he has worked hard to spread Sri Vaishnavam.
11.Madhurakavi Alwar: who is said to be the Sishyan (Student) of Nammalwar is also one among 12 Alwars.
12.Kulasekara Alwar: have a great bhakti towards Sri Ramar have also done Mangalasasanam on the Perumal particularly in Malayala Naatu thriuppathigal.

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