- Whose soul did Arjuna have? Indra's or Nara's ?
Arjuna was biological son of Indra, and to some extent his soul was partly of Sakra (the Indra). Similarly Krishna was 1/6 of Vishnu. From Adi Parva:
... And Hari (lord Vishnu) took up two hairs from his body, one of which
hairs was black and the other white. And those two hairs entered the
wombs of two of the Yadu race, by name Devaki and Rohini. And one of
these hairs viz., that which was white, became Valadeva. And the hair
that was black was born as Kesava's self, Krishna. And those Indras of
old who had been confined in the cave on the Himavat are none else
than the sons of Pandu, endued with great energy. And Arjuna amongst
the Pandavas, called also Savyasachin (using both hands with equal
dexterity) is a portion of Sakra.'
"Vyasa continued, 'Thus, O king, they who have been born as the
Pandavas are none else than those Indras of old. And the celestial Sri
herself who had been appointed as their wife is this Draupadi of
His soul was indeed "Nara". Karna Parva describes about him and Krishna just before the deciding battle with Karna:
When the two Krishnas are excited with wrath, they show regard for
nothing. These two bulls among beings are the Creators of all real and
unreal things. These two are Nara and Narayana, the two ancient and
best of Rishis. There is none to rule over them. They are rulers over
all, perfectly fearless, they are scorchers of all foes. In heaven or
among human beings, there is none equal to either of them.
So we can say that Arjun's soul was amalgamation of Sakra (the Indra) and sage Nara.
For other Mahabharata characters' previous births refer:
What were the previous births of the characters of Mahabharata?
- If Arjuna had Nara's soul (Atma), is this the reason why Krishna exhorted Bhagavadgita to Arjuna, indirectly saying to himself ?( Nara
and Narayana were parts of Lord Vishnu).
This can or cannot be a reason for the same.
Though Arjuna had Nara's soul, he was not self realized about it. But in layman's context, Bhagavad Gita was exhorted to Arjuna because he had surrendered his soul to Krishna.
Now I am confused about my duty and have lost all composure because of
miserly weakness. In this condition I am asking You to tell me for
certain what is best for me. Now I am Your disciple, and a soul
surrendered unto You. Please instruct me.
But again there can be many reasons, which people can come up with:
- Krishna was Arjuna's Saarathy and Arjuna was the one who got
confused before the war.
- Bhagavad Gita was said before
but was forgotten; Hence for the good for the humanity post
Mahabharata, it was recited once more to Arjuna by making him drop
- Yudhishtira was on the right path of Dharma, while Bhima was waiting
for the war since the dice game. Remaining Paandava army were obedient
to Yudhishtira and Kauravas were to Duryodhana. They did not require
any such message giving.
- If assumption in second question is correct, is this the reason behind their friendship?
Possibly yes. During Mahabharata, Nara-Narayana took birth as first cousins, but also dear friends and in a way Guru-Shishya too.
How strong lord krishna and Arjuna's friendship was?