Some portions of Mahabharata depict that Karna learnt Brahmastra from Guru Parashurama, by projecting himself as a Brahmana. Movies, TV shows highlighted this issue, in order to project Karna as victimised person, as inspite of receiving Brahmastra from Guru Parashurama, in the end he had received a curse from Guru Parashurama that Brahmastra will fail him when requires it the most.
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In view of the following reasons, I consider Karna approaching Guru Parashurama as a Brahmana and learning the usage of Brahmastra, as an interpolation.
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a) We have to remember that in Shanti Parva, Sage Narada says to Yudhisthira that Karna approached Guru Drona and asked him to impart the knowledge of Brahmastra.
विद्याधिकमथालक्ष्य धनुर्वेदे धनञ्जयम् । द्रोणं रहस्युपागम्य कर्णो वचनमब्रवीत् ॥
ब्रह्मास्त्रं वेत्तुमिच्छामि सरहस्यनिवर्तनम् । अर्जुनेन समो युद्धे भवेयमिति मे मतिः ॥
समः पुत्रेषु च स्नेहः शिष्येषु च तव ध्रुवम् । त्वत्प्रसादान्न मां ब्रूयुरकृतास्त्रं विचक्षणाः ॥
द्रोणस्तथोक्तः कर्णेन सापेक्षः फल्गुनं प्रति । दौरात्म्यं चापि कर्णस्य विदित्वा तमुवाच ह ॥
ब्रह्मास्त्रं ब्राह्मणो विद्याद्यथावच्चरितव्रतः । क्षत्रियो वा तपस्वी यो नान्यो विद्यात्कथञ्चन ॥
इत्युक्तोऽङ्गिरसां श्रेष्ठमामन्त्र्य प्रतिपूज्य च । जगाम सहसा रामं महेन्द्रं पर्वतं प्रति ॥
स तु राममुपागम्य शिरसाभिप्रणम्य च । ब्राह्मणो भार्गवोऽस्मीति गौरवेणाभ्यगच्छत ॥
One day approached Drona in private and said these words unto him, 'I desire to be acquainted with the Brahma weapon, with all its mantras and the power of withdrawing it, for I desire to fight Arjuna. Without doubt, the affection thou bearest to every one of thy pupils is equal to what thou bearest to thy own son. I pray that all the masters of the science of weapons may, through thy grace, regard me as one accomplished in weapons!'
Thus, addressed by him, Drona, from partiality for Phalguna, as also from his knowledge of the wickedness of Karna, said, 'None but a Brahmana, who has duly observed all vows, should be acquainted with the Brahma weapon, or a Kshatriya that has practised austere penances, and no other.'
When Drona had answered thus, Karna, having worshipped him, obtained his leave, and proceeded without delay to Rama then residing on the Mahendra mountains. Approaching Rama, he bent his head unto him and said, 'I am a Brahmana of Bhrigu's race.'
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Please note carefully that it was narrated above in Shanti parva that Karna approached him on the Mahendra mountains.
- Shanti Parva contains discussions between Bhishma on the bed of arrows and Yudhisthira, after the war. As Bhishma died on the 10th day of the war itself, his giving lecture to Yudhisthira on various issues of Dharma is ruled out. Thus, Shanti Parva itself an interpolation
- The funniest part of the above narration is that Karna met Guru Parashurama on the Mahendra Mountains. In Adi Parva itself it was mentioned that Drona met Guru Parashurama on the Mahendra Mountains, when Parashurama is about withdraw into the Forest for austerities and learnt all DIVINE weapons from him. Thereafter, Parashurama withdrew into the forest. Then, how can Karna meet Parashurama on Mahendra mountains?
b) Parashurama had not remained accessible to anybody, after his imparting knowledge of all DIVINE WEAPONS to Drona.
When Drona was blessed with a son Ashwatthama, he was in poverty. He heard that Guru Parashurama was distributing all the wealth that he had acquired by killing Kshatriyas for 21 times, he had gone with a hope of getting some wealth. By the time he had reached that place, Guru Parashurama already donated entire land to Kashyapa and wealth to the needy and was about to withdraw into the Forest for austerities. Hence, Drona got the knowledge of DIVINE WEAPONS.
Thus addressed by Rama, the son of Bharadwaja replied unto that foremost of all smiters, desirous of giving away the whole of his wealth, 'O thou of multifarious vows, I am a candidate for thy eternal wealth,' 'O thou of ascetic wealth, returned Rama, 'My gold and whatever other wealth I had, have all been given away unto Brahmanas! This earth also, to the verge of the sea, decked with towns and cities, as with a garland of flowers, I have given unto Kasyapa. I have now my body only and my various valuable weapons left. I am prepared to give either my body or my weapons. Say, which thou wouldst have! I would give it thee! Say quickly!'
"Drona answered, O son of Bhrigu, it behoveth thee to give me all thy weapons together with the mysteries of hurling and recalling them.'
"Saying, 'So be it,' the son of Bhrigu gave all his weapons unto Drona,--indeed, the whole science of arms with its rules and mysteries. Accepting them all, and thinking himself amply rewarded that best of Brahmanas then, glad at heart, set out, for (the city of) his friend Drupada.'"
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Here lies the catch. After imparting the knowledge of DIVINE WEAPONS to Drona, Guru Parashurama withdrew into the forest for austerities. Thus, he was not accessible to anyone thereafter.
Hence, Karna approaching Guru Parashurama and receiving the knowledge of Brahmastra is an interpolated story.
Further, Guru Parashurama appearing in different parvas is an another interpolation, as he had already retired to the Forest.
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c) Balance of Mind and control over senses are perquisites for receiving the knowledge of DIVINE WEAPONS.
Learning divine weapons like Brahmastra or Brahmashira requires balance of Mind and control over senses. If Karna had such control, he would have got knowledge of Brahmastra from Drona himself, who was Karna's Guru.
Drona taught so many divine weapons, including Brahmashira, only to Arjuna, who has balance of Mind and control over senses. His only mistake is to impart knowledge of Brahmashira to his son Ashwatthama, out of fatherly affection.
For argument sake let us consider that Guru Parashurama was approached by Karna. Then, Guru Parashurama might have exercised the same caution as his disciple Drona exercised while imparting the knowledge of DIVINE WEAPONS to anyone.
When Drona himself did not impart knowledge of all DIVINE WEAPONS to Karna, can we expect that his Guru Parashurama act in such a careless manner in doing so?
I do not think so. Guru Parashurama might have rejected Karna, though he approached Guru Parashurama as a Brahmana. It is because before imparting knowledge of such a DIVINE WEAPON he should have studied the mental capability of Karna.
Hence, Karna getting Brahmastra is an interpolation.
(d) What is the purpose of Karna getting Brahmastra when Arjuna nullified it so effectively?
When the wheel of his chariot struct, Karna appeals to Arjuna to stop for a while, so that he was standing on ground and Arjuna was in a chariot. Still, he did not stop fighting and continued his fight.
At that moment Karna discharged Brahmastra and Arjuna also discharged Brahmastra and baffled it.
Indeed, remembering the incidents alluded to by Krishna, Dhananjaya blazed up with fury. Then, O king, blazing flames of fire seemed to emanate from all the pores of the angry Partha's body.
The sight seemed to be exceedingly wonderful. Beholding it, Karna, invoking the brahmastra, showered his shafts upon Dhananjaya, and once more made an effort to extricate his car. Partha also, by the aid of the brahmastra, poured arrowy downpours upon Karna. Baffling with his own weapon the weapon of his foe, the son of Pandu continued to strike him.
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So, where is the superiority for Karna over Arjuna, due to his learning Brahmastra by deceiving Guru Parashurama, as Arjuna also effortlessly used Brahmastra?
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(e) We have to remember that as per original Mahabharata, it was Brahmashira, which is ultimate weapon, but not Brahmastra.
As mentioned above only Arjuna, among all the disciples of Drona, knew how to use Brahmashira and withdraw it. Though Ashwatthama knew how to use it, he cannot withdraw it.
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Hence, Karna approaching Guru Parashurama and receiving Brahmastra is an interpolated story.
