One must note that there are two Buddhas. One is the Siddhartha Gautama Buddha and another one is the Vishnu Avatara Buddha. Long ago, there were three demons named Tripuraasuras. Their names were Tarakaksha, Kamalaksha, and Vidyunmaali. They were known as Tripuraasuras because three of them lived in three palaces, namely the golden, silver, and iron palaces.
These Tripuraasuras were due to a boon from Lord Brahma. They asked for a boon that they should live in three different cities of gold, silver, and iron. And they could only be killed when the three cities, or puras, would come in one straight line. And this alignment was only possible once every thousand years. That’s why they were invincible.
Mayasura, the architect for the demons, built the three cities of gold, silver, and iron for the three demons. Taarakaaksha ruled the golden city, Kamalaksha the silver one, and Vidyunmaali ruled the iron city. Like this, they came to be known as Tripuraasuraas. They grew arrogant because of this.
They had even asked for a boon that they could only be killed by a special arrow. They used to trouble the devatas, sages, and all a lot. Frustrated by their torments and nuisance, the devatas and the sages approached Lord Brahma. Lord Brahma, along with the devatas, went to Lord Shiva and asked him to kill the Tripuraasuraas.
Lord Brahma, praying to the Srihari present within Lord Shiva, and the rest of the devatas prayed to Lord Shiva. Lord Shiva listened to them and decided to kill the Tripuraasuraas. Hence, He asked the devatas to give them half of their powers so that He could kill those demons. The devatas did the same. Now, Vishvakarma constructed the chariot for Lord Shiva.
Lord Shiva said, “My charioteer should be superior to me.” And hence, Lord Brahma became the charioteer of Lord Shiva. Lord Vishnu was present in the arrow along with Soma and Surya. Now, here, Mayasura created a Shiva temple in Tarakaaksha’s city and then gave him good upadesha. But he saw that Kali Purusha and Alakshmi had already entered their cities.
And whenever Kali Purusha and Alakshmi enter anything, that thing is sure to be destroyed. So, Mayasura knew he couldn’t save these asuras. Now, Tarakaksha’s son Hari did penance to please Lord Brahma and asked him to make a Mritasanjeevani canal for them. If the dead soldiers were put into that canal, then they would be made alive again.
So, when Lord Shiva came there, the troops of the Tripuraasuraas attacked them. Lord Shiva kept on destroying the army. But these soldiers were thrown into the Mritasanjeevani canal and were made alive again. Lord Shiva remembered Lord Vishnu. Lord Vishnu and Lord Brahma took the form of a cow and a calf and, in front of the demons, drank the whole Mritasanjeevani canal.
Due to the Maya of Lord Vishnu, the Supreme Bhagavan, the demons kept watching, while Lord Vishnu, in the form of a cow, had already drunk the Mritasanjeevani juice. Now, the canal was empty, and hence, Lord Shiva destroyed the army of Tripuraasuras. But then, Tripuraasuraas’ wives were very pativrataas. They didn’t even look at any other man, except their husband and were very devoted to them.
Due to the Paativratya of their wives, Lord Shiva was again facing difficulty in killing the Tripuraasuras. Hence, Lord Vishnu assumed the form of Buddha. Buddha looked like a very handsome man who was very enchanting. He was naked and only wore a kaupeena. He appeared in front of the wives of the Tripuraasuras. The wives saw Buddha and were attracted to their beauty. And that was where their Paativratya was destroyed.
Now, the time had come when the Tripuras, or the three cities, aligned in a straight line, and then Lord Shiva hurled His special arrow, which contained Lord Vishnu, Soma, and Surya’s presence, and then that arrow destroyed the three cities and even the Tripuraasuras. Therefore, Lord Shiva, due to the anugraha of Srihari, destroyed the Tripuraasuras and got the name Tripuraari or Puraari.
But then, as the Kaliyuga started, the asuras gained access to the Vedas and thus got the correct knowledge of the Vedas. Now, the problem was that the demons are inherently evil. No matter what you do, you cannot change their nature cannot be changed. Plus, if they get the correct knowledge, then they would be getting Bhakti in Bhagavan. But their evil nature would still be there.
So, if this happens, they would keep on torturing people and then do Bhakti in Bhagavan. Bhagavan has promised that those who do Bhakti in Him will not be harmed by Him. So, Bhagavan also cannot do anything in this case. So, to prevent this from happening and sending the asuras to Naraka, due to their evil nature, which is inherent, Bhagavan deludes them onto the wrong path.
So, when this started happening in the Kaliyuga, the first among the Tripuraasuras was born as Shuddhodana and Jina in the Kikata-named region, in Gaya. So, they were following the Vedic procedures and were gaining the correct knowledge. This wasn’t acceptable to the devatas. So, the devatas, led by Lord Brahma and Lord Shiva, came to the northern coast of Ksheerasaagara and pleaded with Bhagavan Vishnu to do something.
Lord Vishnu, on hearing the requests of the devatas, Lord Vishnu smiled and assumed the form of a beautiful, cute and handsome baby. Here, another boy was born to Shuddhodana and Anjana. He was Siddhartha. But Lord Vishnu replaced Shuddhodana's baby Siddhartha with His own baby form. He threw that baby far away into Gaya.
Shuddhodana, unaware of this exchange, assumed that the baby form of Lord Vishnu was their son, whereas their actual son was replaced by the baby form of Lord Vishnu, known as Buddha. Now, when Shuddhodana was doing the Jaataka Karma of the baby, at that time, that baby laughed and said, “I am Buddha. You are all engaged in these Vedic acts. Well, as the Supreme Being, let me tell you that all these Vedic tasks are invalid, and the Vedas are not the authority, or are apramaana. Everything is Shoonya, and is asat.”
But then, nobody was ready to believe what that baby was saying. But then, Lord Vishnu, in the form of Buddha, remembered the devatas. The devatas came there and attacked Buddha with their weapons. But Buddha swallowed all of them. He even swallowed Lord Shiva’s trishoola. Lord Vishnu, who was non-different from Buddha, threw His Sudarshana Chakra at Buddha, and Buddha sat on the Sudarshana Chakra.
The devatas finally bowed down to Buddha and departed to their lokas. This convinced Shuddhodana and Jina that Buddha was the Supreme, and they followed the teachings of Buddha, left their Vedic Dharma, and hence got deluded by false knowledge. After deluding Shuddhodana and his followers, Buddha came to the Devaloka.
There, Lord Narayana, in the form of Buddha, revealed the true Buddha philosophy. He said, “Oh, devatas! I am here now to reveal the true Buddha philosophy. So, listen to me carefully.” Thus saying, Buddha roopi Bhagavan started giving the upadesha to the devatas.
Buddha roopi Narayana said, “The units of time and their attributes get over within a short period of time by their very nature. Therefore, although they are eternal, they are considered momentary. Keeping this special attribute in mind, I informed them that everything was momentary. An object and its attributes are inseparable, and therefore they possess the ability to self-regulate. Therefore, there is no contradiction in saying that a substance is momentary as well as fixed.”
He said, “I said, ‘The Vedas are Apramaana.’ But here ‘A’ in Apramaana stands for me. I am known by the name ‘A’. And hence, the statement Apramaana means, ‘I alone am the pramaana or am known by the true Vedas.’ Since I am independent, I am known by the name ‘Jna’. So, that’s why this universe is ananeeya to me. In other words, this universe manifests from me, because it is dependent on me. So, this sentient universe is Jnaanaatmaka. And of course it is self-established that the sentient beings are jnaanatmaka.”
Buddha roopi Narayana said, “I said that the world is Shoonya. Since I am the very personification of pure and unadulterated bliss, I am known by the name Shoo. Since I even do the niyamana, or creation of all, I am known as ‘Nya’. And hence, since I am the personification of pure bliss and create all, I am the source of all, and hence, I am known as Shoonya. Since the universe is controlled by me as Shoonya, the world is Shoonya.”
He said, “Since I am away from all the defects and am unique, therefore, I am known as ‘A’. Since everything is born from the ‘A’ form of mine, all of these things are known as Abhaava. Since everything is destroyed by me only at the time of pralaya, this universe is known as Asat. In this way, my teachings are to be (correctly) understood. There is nothing unacceptable in all of this.”
And thus, Buddha roopi Paramatma taught the devatas the correct meaning of Buddha Philosophy. After saying this, Lord Buddha stayed along with the devatas in one form. And in another form, He went to His own Loka, which is Vaikuntha Loka, and stayed there in one form. Thus, this was the story of Lord Buddha.
Later, Buddha roopi Narayana gave the Upadesha of the Prashaanta Vidya to the devatas, which was the correct knowledge to understand Bhagavan, and is the very essence of the Vedas. This was totally different and opposite to the knowledge He gave to Shuddhodana and Jina. The knowledge the Buddha gave to Shuddhodana and Jina was a delusional knowledge, whereas the knowledge given to devatas (like the correct interpretations of the teachings of Buddha roopi Narayana and the Prashaanta Vidya), was the correct knowledge leading to Moksha. And the one who follows this Prashaanta Vidya attains Moksha in the end.
[Source: The Mahabharata Tatparya Nirnaya of SriMadhvacharya]
Thus, Buddhavatara is the Mohaka Avatara of Lord Vishnu, taken to delude the demons into the wrong path, as stated in the Bhagavata, while describing the 24 avatars of Lord Vishnu.
ततः कलौ सम्प्रवृत्ते सम्मोहाय सुरद्विषाम् ।
बुद्धो नाम्नाञ्जनसुतः कीकटेषु भविष्यति ॥ २४ ॥
The verse (tataḥ kalau sampravṛtte...) foretells that at the outset of Kali-yuga, the Lord will incarnate as Buddha, the son of Añjanā, in the region of Kīkaṭa (Gayā) to delude those envious of the devatas (in other words, to delude the demons).
[Bhagavata Purana]
नमो बुद्धाय शुद्धाय दैत्यदानवमोहिने ॥
I bow down to Lord Buddha, who is pure and is the deluder of the demons, by giving them false knowledge.
[Bhagavata Purana, Akrura Stuti]
तथा बुद्धत्वमपरं नवमं प्राप्स्यतेऽच्युतः ।
शान्तिमान्देवदेवेशो मधुहन्ता मधुप्रियः ॥ २१ ॥
तेन बुद्धस्वरूपेण देवेन परमेष्ठिना ।
भविष्यति जगत्सर्वं मोहितं सचराचरम् ॥ २२ ॥
Achyuta, the Lord of the gods, the slayer of Madhu, shall attain another manifestation as Buddha, the ninth incarnation. In that Buddha form of the Supreme Lord, the entire universe, including all moving and non-moving beings, shall become deluded.
[Skanda Purana, Reva Khaṇḍa, Chapter 151, Verses 21–22]
Lord Narayana says in the Mahabharata:
ततः कलियुगस्यादौ द्विजराजतरुं श्रितः ।
भीषया मागधेनैव धर्मराजगृहे वसन् ॥ ४२ ॥
काषायवस्त्रसंवीतो मुण्डितः शुक्लदन्तवान् ।
शुद्धोदनसुतो बुद्धो मोहयिष्यामि मानवान् ॥
Then, at the beginning of the Kali Yuga, taking shelter in the Magadha region (Gaya), wearing saffron-colored robes, with a shaven (bald) head and white teeth, manifesting as the son of Shuddhodana, I (as Buddha) shall bewilder humanity.
[Mahabharata, Shanti Parva]
अग्निंरुवाच
वक्ष्ये बुद्धौतारञ्च पठतः शृण्वतोऽर्थकृत् ।
पुरा देवासुरे युद्धे दैत्यैर्देवाः पराजिताः ॥ १ ॥
शरणं शरणं याता विष्णुं मन्वादयो हरिम् ।
मायातनुं समाश्रित्य शुद्धोदनसुतोऽभवत् ॥ २ ॥
मोहयामास दैत्यांस्तांस्त्याजिता वेदधर्मकम् ।
ते च बौद्धा बभूवुर्हि तेभ्योऽन्ये वेदवर्चिताः ॥ ३ ॥
Agni said:
I shall now describe the incarnation of Buddha...In ancient times, a war broke out between the Devas and the Asuras, and the Devas were utterly defeated. They, along with Manu and others, sought absolute refuge in Lord Hari (Vishnu). Taking recourse to a deceptive/illusory physical form (Māyā-tanu), the Lord manifested as the son of Shuddhodana. He completely bewildered the Daityas and caused them to abandon the Vedic path (Veda-dharmakam). Others who followed those teachings also became completely bereft of the Vedas.
[Agni Purana, Adhyaya 16, Shlokas 1–3]
इत्युक्त्वा भगवांस्तेभ्यो महामोहमयंतनुम् ।
प्रदाय प्राह चांशोऽयं भवतां उपकारकृत् ॥ ४१ ॥
गच्छतेमं गृहीत्वाद्य स वः कार्यं करिष्यति ।
मोहायमाना दैतेयां वेदमार्गविरोधकृत् ॥ ४२ ॥
Thus, Bhagavan spoke and told the devatas: This is my avatara as Buddha, which I am taking for your welfare. Go, take Him with you and He will do the work and will delude the demons and will take them away from the Vedic Dharma, which would lead to Moksha.
[Vishnu Purana, Book 3, Chapter 17]
ततो गत्वा स ददृशे नर्मदातीरवर्तिनः ।
तपस्यतोऽसुरान् घोरान् धर्मराजजिगीषया ॥ १ ॥
उवाच मधुरं वाक्यं नैराश्यात्मकं आदरात् ।
भवद्भिः क्रियते चैतत्तापायैतद्गतार्थताम् ॥ २ ॥
Thereupon, proceeding to the banks of the Narmada River, that Māyāmoha Buddha form beheld the fierce Asuras performing severe penances with the intense desire to conquer the King of the Devas. [1] Approaching them with feigned respect, He spoke sweet words that were purely nihilistic in nature (Nairāṣyātmakam), saying: "Why do you practice these torturous penances? They lead to nothing but misery; understand that the universe holds no absolute permanence."
[Vishnu Purana, Book 3, Chapter 8]
ततः कलौ संप्रवृत्ते हरिस्तु संमोहनार्थं चासुराणां खगेन्द्र ।
नाम्ना बुद्धो कीकटेषु प्रजातो वेदप्रमाणं निराकर्तुमेव ॥
When Kali Yuga began, Hari was born in the land of Kikata under the name Buddha, for the purpose of deluding the Asuras and rejecting the authority of the Vedas.
[Garuda Purana, 2.64.26]
कलौ प्राप्ते यथा बुद्धो भवेन्नारायणः प्रभुः ॥
When Kali Yuga arrives, the Supreme Lord Narayana becomes Buddha.
[Narasimha Purana, Chapter 36, Verse 9]
दैत्यानां नाशनार्थाय विष्णुना बुद्धरूपिणा ।
बौद्धशास्त्रमसत्प्रोक्तं नग्ननीलपटादिकम् ॥
For the destruction of the Daityas, the false Buddhist teachings, including those of the naked and blue-robed orders, were proclaimed by Vishnu in the form of Buddha
[Padma Purana, Uttarakhaṇḍa, 236.6]
This is the true story of Buddhavatara as per the Shaastras. This Buddha is an incarnation of Lord Vishnu and not the Gautama Buddha. Gautama Buddha came later, after this Buddha roopi Narayana, and followed the teachings that Buddha roopi Narayana gave to Shuddhodana and Jina. Talking about Vishnu and Krishna, both are the same Bhagavad-roopas.
Vishnu is non-different from Krishna in all aspects, such as mood, strength, beauty, valour, opulence, etc. Lord Vishnu, who is full of all attributes, with His transcendental body and powers, incarnated as Krishna, the son of Devaki and Vasudeva, to destroy Adharma and to establish Dharma. Hence, there is no difference between Buddha roopi Narayana, Lord Vishnu, and Lord Krishna.
अवतारा ह्यसंख्याता विष्णोर्नारायणस्य च ।
स्वयं नारायणास्ते ते नाणुमात्रं विभिद्यते ॥
The incarnations of Vishnu, that is, of Narayana, are innumerable. They are themselves Narayana; they do not differ from Him even by the slightest measure.
बलतोरूपतश्चापि गुणतश्च कथञ्चन ।
अनन्तोनन्तगुणतः पूर्णो विष्णुर्न चान्यथा ॥
In power, form, and qualities, they do not differ in any way. Vishnu is infinite, endowed with infinite qualities, and ever complete.
[Garuda Purana, 2.64.29–30]
Hope this helps!
Jay SriRam!
ShriBuddha-Roopi-Narayana Abhinna ShriKrishnarpanamastu!