Pradyumna: Translation: "Sūta Gosvāmī said: Arjuna, the celebrated friend of Lord Kṛṣṇa, was grief stricken because of his strong feeling of separation from Kṛṣṇa, over and above all Mahārāja Yudhiṣṭhira's speculative inquiries." SB 1.15.1
Prabhupāda: So evaṁ kṛṣṇa sakhaḥ kṛṣṇo. Arjuna's name is Kṛṣṇa-sakha, and he is also called sometimes Kṛṣṇa, because Arjuna's bodily feature was almost similar to Kṛṣṇa's bodily feature. So, he was morose, being separated from Kṛṣṇa, and his elder brother was suggesting whether he was morose for this reason or that reason or this reason. Actually, he was unhappy on account of being separated from Kṛṣṇa. Similarly, not only Arjuna, all of us, we are also, as Kṛṣṇa, Arjuna, he is also a living entity, we are also living entity. So we are also unhappy, because we are separated from Kṛṣṇa. These modern philosophers or scientists, they may suggest that they may go on thinking otherwise that they can improve the world situation in their own way, but that is not possible. We are unhappy on account of being separated from Kṛṣṇa. They do not know that. Just like a child, a child is crying, nobody can say why he is crying, but actually a child is generally in crying condition being separated from the mother.
So the, not only it is the question of Arjuna or Kṛṣṇa, everyone of us. In the Upaniṣad it is said that Paramātmā, Kṛṣṇa, and the living entity, they are sitting on the same tree, samāni vṛkṣe. One living entity is eating the fruit of the tree, and the other living entity is simply witnessing, anumantā. So Kṛṣṇa, He's situated in everyone's heart, īśvaraḥ sarva-bhūtānāṁ hṛd-deśe 'rjuna tiṣṭhati BG 18.61. Because without His sanction, the living entity cannot do anything. Sarvasya cāhaṁ hṛdi sanniviṣṭo BG 15.15, Kṛṣṇa says that "I am seated in everyone's heart." So, the living entity wants to do something out of his own whims, Kṛṣṇa says, or Kṛṣṇa gives good consultation that "This will not make you happy, don't do this." But he is persistent, he will do it. Then Kṛṣṇa sanctions, Paramātmā, "All right, you do it, at your risk." This is going on. Everyone of us (is) very intimately connected with Kṛṣṇa, and Kṛṣṇa is sitting in everyone's heart. Kṛṣṇa is so kind, that He is simply waiting, "When this rascal will turn his face towards Me." He's simply looking... He's so kind. But we living entities, we are so rascal, we shall turn our face to everything except Kṛṣṇa. This is our position.