Traditional account

This has come down to us through generations by way of hearsay. This is mostly based on the earliest written poetic work on the life of Arunagirinathar entitled, "Arunagirinathar Swamigal Puranam" by a saintly Swami — Thandapani Swamigal — who also goes by the names of Murugadasa Swamigal and Thiruppugal Swamigal (1839-1898). He composed the puranam about Arunagirinathar about the year 1865. It is as follows:

Arunagiri was born in Thiruvannamalai, Tamil Nadu, and is believed to have lived in the middle of the fifteenth century A.D. He was the son of a Daasi (a dancing girl) named Muthu and had an elder sister by name Adhi. It is also said that Arunagiri was born to Muthu from the famous mystic saint of Tamil Nadu, Pattinathar, in an unusual manner.

When the boy attained the age of five, he was put to school. At his seventh year of age, his mother passed away. She loved the boy so much that while she was in the death-bed, she entrusted Arunagiri to the care of her daughter (i.e., the elder sister of Arunagiri) with specific instructions not to do anything that would displease him. Arunagiri's sister understood the anxious mental condition of her mother and gave her a word of promise that she would leave nothing undone to please Arunagiri and keep him happy.

As Arunagiri grew in age, he found the company of women more pleasing than his studies, which he virtually neglected and sought the pleasures of enchanting courtesans. Slowly, he became a confirmed debauch.

His sister, who came to know of this conduct of Arunagiri, tried her best to extricate him from the traps of public women. But nothing could prevent Arunagiri from his infatuated love for women. He must have his ways at any cost.

The poor sister could not do anything drastic, lest she should be harsh to Arunagiri or displease him, which would mean breaking her promise to her mother. Thus, did Arunagiri indulge in sex heedlessly and depleted all the wealth hoarded by his mother.

Slowly, he began to snatch away, one by one, the ornaments of his sister, sometimes with her knowledge and sometimes otherwise. The helpless lady could do nothing except pray to the Lord to save Arunagiri.

In the meantime, Arunagiri contracted many diseases and suffered much. Yet he would not learn a lesson. He squandered all his sister's wherewithal and left her a complete pauper. But he would yet demand money from her to satisfy his sexual appetite and if she pleaded helplessness, he would threaten her of sinking before her very eyes.

In spite of her being reduced to this most pitiable condition, she could not imagine displeasing Arunagiri. But, now she was utterly helpless. She grew desparate and said, "Brother! I had been helping you with all that I had. But now I find no means to help you. Yet I cannot think of displeasing you. Brother, tell me what can I do? Well, only one means is left now. Though we are born of the same mother, our fathers are dfferent. Hence, the pleasure that you seek from a woman, you can find with me!"

She would have continued, but her throat choked; she became silent.

Lo! These words entered Arunagiri's heart like sharp arrows and shook his very being so fundamentally that he repented with a contrite heart for all his past misdeeds and wept bitterly. And in a moment he decided to put an end to his life as an expiation for all the sins committed by him.

Before his sister could understand as to what was happening to Arunagiri, he ran posthaste, climbed the tower of the Arunachala Temple, repented with an honest feeling, cried aloud the Name of the Lord, "Muruga! Muruga! Muruga!" and jumped down, to put an end to his miserable existence and thereby be freed from his sins.

Who can understand the ways of the Lord! Ere Arunagiri fell towards the ground, when there stood the Lord with His outstretched hands and held Arunagiri in His warm embrace. Yet, Arunagiri knew not anything.

With His Vel, the Lord wrote His sacred Mantra on Arunagiri's tongue, gave him a Japa Mala, named him "Arunagiri-naathar," and commanded him to sing His glories. Arunagirinathar hesitated. The Lord Himself then gave the first line as:

From Thiruppugal #6: Transliteration: muthai-tharu pathi thiru-Nagai athi-kiRai sathich-saravaNa muthi-koru vithu-guru-bara ...... enavOthum Meaning: Deivayanai's Lord! O Saravanabhava, Sakthi-Vel holding! O Guru Supreme! O Seed (Source) for Moksha gaining! — Thus, sing. See Also: Full text (Tamil & English) of "muthai-tharu pathi thiru-Nagai" Listen to "muthai-tharu pathi thiru-Nagai" (courtesy of Kaumaram.org) For the complete collection of Thiruppugal songs, click here

The Lord then disappeared. Arunagirinathar stood there totally transformed. He adopted the life of a renunciate. The erstwhile sinner shone now as a saint. His body was cured of all its diseases; his mind was purged of all impurities; his heart was brimming with devotion and he was in a highly ecstatic mood.

Arunagirinathar, having now got the complete grace and command of the Lord, at once completed the song. He was full of expression, love, and supreme devotion. As the waters of a reservoir rush forth when the floodgate is thrown open, wisdom and love flowed through the Saint in the form of Thiruppugal songs.

Arunagirinathar went from tower to tower of the Arunachaleshwarar Temple and poured forth poems in exquisite Tamil. He then went round the streets of Thiruvannamalai, singing the glories of the Lord in diverse ways. He was God-intoxicated out and out, and started on a pilgrimage to all holy places, singing the Thiruppugal ("Glory of God"), wherever he went, enjoying various kinds of divine experiences at different places.

To continue reading about Arungirinthar's life, click here

Next the author recounts the "historical" version of the Life of Arunagirinathar below (using sanskrit works, historical inscriptions around Thiruvannamalai, etc).

source:http://www.skandagurunatha.org/saints/arunagirinathar.asp