Srimad-Bhagavatam: Canto 4 - Chapter 1 - Verse 4


ध्रुवो भ्रातृवधं श्रुत्वा कोपामर्षशुचार्पित: । जैत्रं स्यन्दनमास्थाय गत: पुण्यजनालयम् ॥ ४ ॥


dhruvo bhrātṛ-vadhaṁ śrutvākopāmarṣa-śucārpitaḥjaitraṁ syandanam āsthāyagataḥ puṇya-janālayam


When Dhruva Mahārāja heard of the killing of his brother Uttama by the Yakṣas in the Himālaya Mountains, being overwhelmed with lamentation and anger, he got on his chariot and went out for victory over the city of the Yakṣas, Alakāpurī.


Dhruva Mahārāja’s becoming angry, overwhelmed with grief, and envious of the enemies was not incompatible with his position as a great devotee. It is a misunderstanding that a devotee should not be angry, envious or overwhelmed by lamentation. Dhruva Mahārāja was the king, and when his brother was unceremoniously killed, it was his duty to take revenge against the Yakṣas from the Himālayas.