So Kṛṣṇa has enemies. Arisudana. And He has to kill them. Kṛṣṇa has got two businesses: paritrāṇāya sādhūnāṁ vināśāya ca duṣkṛtam (BG 4.8). Miscreants. They are miscreants. The demons who challenge Kṛṣṇa, who wants to compete with Kṛṣṇa, who want to share with the property of Kṛṣṇa, they are all enemies of Kṛṣṇa, and they should be killed. So killing business is all right here for the enemies, not ordinarily. Then the next question is, "All right, enemies you can kill, admitted. But how You advise me to kill my gurus?" Gurūn ahatvā. But if for Kṛṣṇa's sake, if there is need, you have to kill your guru also. That is the philosophy. For Kṛṣṇa's sake. If Kṛṣṇa wants, then you cannot . . . if Kṛṣṇa wants that you should kill your guru, then you have to do it. That is Kṛṣṇa consciousness. Of course, Kṛṣṇa will not ask you to kill guru, but . . . because guru and Kṛṣṇa is the same. Guru-kṛṣṇa-kṛpāya (CC Madhya 19.151). We get Kṛṣṇa consciousness through the mercy of guru and Kṛṣṇa.
So real guru is never to be killed, but the so-called guru has to be killed. The so-called, pseudo guru, false guru, he should be killed. Just like Prahlāda Mahārāja. While Prahlāda Mahārāja . . . he was standing. Here is . . . Nṛsiṁhadeva is killing his father. Father is guru. Sarva-devamayo guruḥ (SB 11.17.27). Similarly, father is also guru, at least, official guru. Materially he is guru. So how Prahlāda Mahārāja allowed Nṛsiṁha-deva to kill his guru? He's father. Everyone knows that Hiraṇyakaśipu is father. Would you like to see that your father is being killed by some person, and you'll stand? You will not protest? Is that your duty? No, that is not your duty. When your father is attacked, you must protest. At least, if you are unable, you must fight. You first of all lay down your life: "How is that, my father is being killed in my front?"
That is your duty. But Prahlāda Mahārāja did not protest. He could have requested—he is devotee—"My dear Sir, Prabhu, my Lord, You can excuse my father." He did it. But he knew that, "My father is not being killed. It is the body of the father." Later on he begged for his father in a different way. First of all, when Nṛsiṁha-deva was angry, He was killing the body, he knew that "The body is not my father. The soul is my father. So let the Lord satisfy Himself by killing the body of my father; then I shall save him."