Again, according to his autobiography, shortly before Yogananda left for America in 1920, Babaji came to his home in Calcutta, where the young monk sat deeply praying for divine assurance regarding the mission he was about to undertake. Babaji said to him: "Follow the behest of your guru and go to America. Fear not; you shall be protected. You are the one I have chosen to spread the message of Kriya Yoga in the West."
There are very few accounts of Babaji's childhood. One source of information is the book Babaji and the 18 Siddha Kriya Yoga tradition by Marshal Govindan. According to Govindan, Babaji was named Nagarajan (king of serpents) by his parents. V.T. Neelakantan and S.A.A. Ramaiah founded on 17 October 1952, (they claim – at the request of Babaji) a new organization, "Kriya Babaji Sangah," dedicated to the teaching of Babaji's Kriya Yoga. They claim that in 1953 Mahavatar Babaji told them that he was born on 30 November 203 CE in a small coastal village now known as Parangipettai, Cuddalore district of Tamil Nadu, India. Babaji's Kriya Yoga Order of Acharyas Trust (Kriya Babaji Sangah) and their branch organizations claim his place and date of birth. He was a disciple of Bogar and his birth name is Nagarajan.
In Paramahansa Yogananda's Autobiography of a Yogi, many references are made to Mahavatar Babaji, including from Lahirī and Sri Yukteshwar. In his book The Second Coming of Christ, Yogananda states that Jesus Christ went to India and conferred with Mahavatar Babaji. This would make Babaji at least 2000 years old. According to Govindan's book, Babaji Nagaraj's father was the priest of the village's temple. Babaji revealed only those details which he believed to be formative as well as potentially instructive to his disciples. Govindan mentioned one incident like this: "One time Nagaraj's mother had got one rare jackfruit for a family feast and put it aside. Babaji was only 4 years old at that time. He found the jackfruit when his mother was not around and ate it all. When his mother came to know about it, she flew in blind rage and stuffed a cloth inside Babaji's mouth, nearly suffocating him, but he survived. Later on he thanked God for showing him that she was to be loved without attachment or illusion. His Love for his mother became unconditional and detached."
When Nagaraj was about 5 years old, someone kidnapped him and sold him as a slave at Calcutta (Now Kolkata). His new owner however was a kind man and he freed Nagaraj shortly thereafter. Nagaraj then joined a small group of wandering sannyāsin due to their radiant faces and love for God. During the next few years, he wandered from place to place, studying holy scriptures like the Vedas, Upanishad, Mahabharata, Ramayana, Bhagavad Gita.
According to Marshall Govindan's book, at the age of eleven, he made a difficult journey on foot and boat with a group of ascetics to Kataragama, Sri Lanka. Nagaraj met Siddha Bhogarnathar and became his disciple. Nagaraj performed intensive yogic sadhana for a long time with him. Bhogarnathar inspired Nagaraj to seek his initiation into Kriya Kundalini Pranayam from Siddha Agastya. Babaji became a disciple of Siddha Agastya. Nagaraj was initiated into the secrets of Kriya Kundalini Pranayama or "Vasi Yogam". Babaji made a long pilgrimage to Badrinath and spent eighteen months practising yogic kriya taught to him by Siddha Agastya and Bhogarnathar. Babaji attained self-realization shortly thereafter.
It is claimed that these revelations were made by Babaji himself to S.A.A. Ramaiah, a young graduate student in geology at the University of Madras and V.T. Neelakantan, a famous journalist, and close student of Annie Besant, President of the Theosophical Society and mentor of Krishnamurti. Babaji was said to have appeared to each of them independently and then brought them together to work for his Mission in 1942.
The first reported encounter with Mahavatar Babaji was in 1861, when Shyāmacharan Lahirī (called "Mahāsaya" by disciples, devotees, and admirers) was posted to Ranikhet in his work as an accountant for the British government. One day while walking in the hills of Dunagiri above Ranikhet, he heard a voice calling his name. Following the voice up the mountain, he met a "tall, divinely radiant sadhu." He was amazed to find that the sadhu knew his name. This sadhu was Mahavatar Babaji.
Mahavatar Babaji told Lahirī that he was his guru from the past, then initiated him into Kriya Yoga and instructed Lahiri to initiate others. Lahiri wanted to remain with Mahavatar Babaji, who told him instead that he must return to the world to teach Kriya Yoga and that "Kriya Yoga sadhana would spread through the people of the world through his (Lahiri's) presence in the world."
Lahirī reported that Mahavatar Babaji did not give his name or background, so Lahiri gave him the title "Mahavatar Babaji." Many sadhus in India are called Babaji, and sometimes even "Babaji Maharaj", which has caused confusion between Mahavatar Babaji and other sadhus with similar names.
Lahirī had many meetings with Mahavatar Babaji, recounted in several books, including Paramhansa Yogananda's Autobiography of a Yogi, Yogiraj Shyama Charan Lahiri Mahasaya (Lahiri's biography), and Purana Purusha: Yogiraj Sri Shama Churn Lahiri, among others.
The references of Sri Lahiri mahasaya in Sampoorna Sripada Vallabha Charitam, as the guru of Sri Shirdi Saibaba and initiating him to kriya yoga.
Several disciples of Shyāmacharan Lahirī also said that they had met Babaji. Through discussion with each other, and the fact that some of these encounters included two or more witnesses, they confirmed that the person they saw was the same sadhu that Lahirī called Mahavatar Babaji.
In 1894, at the Kumbha Mela in Allahabad, Yukteswar Giri, a disciple of Lahirī, met Mahavatar Babaji. He was surprised by the striking resemblance between Lahirī and Mahavatar Babaji. Others who met Babaji also commented on the resemblance. It was at this meeting that Mahavatar Babaji instructed Sri Yukteswar to write the book that was to become Kaivalya Darshanam, or The Holy Science. Yukteswar had two more meetings with Mahavatar Babaji, including one in the presence of Lahiri Mahasaya.
Pranabananda Giri, another disciple of Lahirī, also met Mahavatar Babaji in the presence of Lahirī, at Lahirī's home. Pranabananda asked Mahavatar Babaji his age. Mahavatar Babaji responded that he was about 500 years old at that time.
Keshabananda, a disciple of Lahirī, tells of meeting Mahavatar Babaji in the mountains near Badrinath around 1935, after he became lost wandering in the mountains. At that meeting, Pranabananda reported that Babaji gave him a message for Paramahansa Yogananda, that "I won't see him this time, as he is eagerly hoping; but I shall see him on some other occasion." In his book Autobiography of a Yogi, Paramahansa Yogananda wrote that Mahavatar Babaji visited him before his journey to America and addressed him saying, "You are the one I have chosen to spread the message of Kriya Yoga in the West."
Other disciples of Lahirī who reported meetings with Mahavatar Babaji include Kebalananda Giri and Ram Gopal Muzumdar, who recounted meeting Mahavatar Babaji and his sister, whom he called Mataji. In addition, a disciple of Trailanga Swami, Shankari Mata (also called Shankari Mai Jiew) met Mahavatar Babaji while visiting Lahiri Mahasaya.
Legendary powers and age have been attributed to Mahavatar Babaji by the disciples of Lahirī. These stories have led many to believe that Mahavatar Babaji is a legendary person, rather than a real sadhu that was seen by numerous witnesses from 1861 to 1935.
Paramahansa Yogananda, in his Autobiography, described Mahavatar Babaji's role on earth :
The Mahavatar is in constant communion with Christ; together they send out vibrations of redemption, and have planned the spiritual technique of salvation for this age. The work of these two fully-illumined masters–one with the body, and one without it–is to inspire the nations to forsake suicidal wars, race hatreds, religious sectarianism, and the boomerang-evils of materialism. Babaji is well aware of the trend of modern times, especially of the influence and complexities of Western civilization, and realizes the necessity of spreading the self-liberations of yoga equally in the West and in the East.
In addition, Babaji is reputed to be ageless, according to some accounts, and about 500 years old around the late 1800s, according to Pranabananda. Yogananda reports that, according to the disciples of Lahirī, nobody knows Babaji's age, family, place of birth, true name, or other details "dear to the annalist's heart."
According to Yogananda's autobiography, he has a sister called Mataji (meaning "Holy Mother") who also has lived throughout the centuries. Her level of spiritual attainment is comparable to her brother's, and she lives in a state of spiritual ecstasy in an underground cave. Although only three pages in the book are dedicated to her, she is described by Ram Gopal as "young and surpassingly lovely" as well as a "glorious woman."
Yogananda frequently prayed out loud to "Babaji-Krishna."