Tamāla Kṛṣṇa: "O son of Pṛthā, do not yield to this degrading impotence (BG 2.3)."
Prabhupāda: Hm. Degrading impotence. He doesn't want to see (chuckling) His devotee a coward and impotent. So this so-called qualification, impotency and niggard, that is not qualification for devotee. He must be very, in every way, very expert and fit. Kṛṣṇa wants to see. Yes. Go on.
Tamāla Kṛṣṇa: "It does not become you. Give up such petty weakness of heart and arise, O chastiser of the enemy."
Prabhupāda: He's specially addressing, "chastiser of the enemy." Where there is no excuse, you must be chastiser. Not that "Because I have become Kṛṣṇa conscious, I'll be very humble." You must be humble, but in need, if there is need, you shall be thunderbolt. That is Kṛṣṇa instructing.
Tamāla Kṛṣṇa: "Arjuna said: O killer of Madhu, Kṛṣṇa, how can I counterattack with arrows in battle personalities like Bhīṣma and Droṇa, who are worthy of my worship (BG 2.4)?"
Prabhupāda: Of course, all explanation are not there. Here, these words, Kṛṣṇa addressed Arjuna, "chastiser of enemies." And Arjuna addresses Kṛṣṇa, "Madhusūdana," or the killer of the demon Madhu. "Yes, You are addressing me as chastiser of enemy, but do You think my grandfather, my teacher, they are my enemies? You killed demon Madhu, therefore Your name is Madhusūdana, but You are asking me to kill my grandfather and teacher." That is the hint. "It is all right that Your name is Madhusūdana. You killed one demon whose name was Madhu, but You are asking me, Bhīṣmasūdana? Bhīṣma is my grandfather. And Droṇasūdana?" Sūdana means killer. "So how can I be that?" That is the answer.