Śrīmad-Bhāgavatam · Text 4.12.43
Who is speaking and story frame
य: क्षत्रबन्धुर्भुवि तस्याधिरूढ-
मन्वारुरुक्षेदपि वर्षपूगै: ।
प्रसाद्य वैकुण्ठमवाप तत्पदम् ॥ ४३ ॥ षट्पञ्चवर्षो यदहोभिरल्पै:
yaḥ kṣatra-bandhur bhuvi tasyādhirūḍham
anv ārurukṣed api varṣa-pūgaiḥ
ṣaṭ-pañca-varṣo yad ahobhir alpaiḥ
prasādya vaikuṇṭham avāpa tat-padam
Dhruva Mahārāja attained an exalted position at the age of only five or six years, after undergoing austerity for six months. Alas, a great kṣatriya cannot achieve such a position even after undergoing austerities for many, many years.
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