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…Śiśupāla went crazy because of Kṛṣṇa’s being elected the supreme first-worshiped person in that meeting, and he spoke so irresponsibly that it appeared that he had lost all his good fortune. Being overcast with misfortune, Śiśupāla continued to insult Kṛṣṇa further, and Lord Kṛṣṇa patiently heard him without protest. Just as a lion does not care when a flock of jackals howl, Lord Kṛṣṇa remained silent and unprovoked. Kṛṣṇa did not reply to even a single accusation made by Śiśupāla, but all the members present in the meeting, except a few who agreed with Śiśupāla, became very agitated because it is the duty of any respectable person not to tolerate blasphemy against God or His devotee. Some of them, who thought that they could not properly take action against Śiśupāla, left the assembly in protest, covering their ears with their hands in order not to hear further accusations. Thus they left the meeting condemning the action of Śiśupāla. It is the Vedic injunction that whenever there is blasphemy of the Supreme Personality of Godhead, one must immediately leave. If he does not do so, he becomes bereft of his pious activities and is degraded to the lower condition of life.
All the kings present, belonging to the Kuru dynasty, Matsya dynasty, Kekaya dynasty and Sṛñjaya dynasty, became very angry and immediately took up their swords and shields to kill Śiśupāla. Śiśupāla was so foolish that he did not become even slightly agitated, although all the kings present were ready to kill him. He did not care to think of the pros and cons of his foolish talking, and when he saw that all the kings were ready to kill him, instead of stopping, he stood to fight with them and took up his sword and shield. When Lord Kṛṣṇa saw that they were going to engage in fighting in the arena of the auspicious Rājasūya yajña, He personally pacified them. Out of His causeless mercy He Himself decided to kill Śiśupāla. When Śiśupāla was abusing the kings who were about to attack him, Lord Kṛṣṇa took up His disc, which was as sharp as the blade of a razor, and immediately separated the head of Śiśupāla from his body.
…Śukadeva Gosvāmī assured Mahārāja Parīkṣit that the pastimes of Lord Kṛṣṇa–the killing of Śiśupāla and Jarāsandha and the releasing of the imprisoned kings–are all transcendental vibrations, and anyone who hears these narrations from the authorized persons will be immediately freed from all the reactions of the sinful activities of his life.
Kṛṣṇa, The Supreme Personality of Godhead 1970 Edition
By His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
Vol. 2, Chapter 19
The Deliverance of Śiśupāla
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