Srimad-Bhagavatam: Canto 12 - Chapter 1 - Verse 49


तस्मात् सर्वात्मना राजन् हृदिस्थं कुरु केशवम् ।म्रियमाणो ह्यवहितस्ततो यासि परां गतिम् ॥ ४९ ॥


tasmāt sarvātmanā rājanhṛdi-sthaṁ kuru keśavammriyamāṇo hy avahitastato yāsi parāṁ gatim


Therefore, O King, endeavor with all your might to fix the Supreme Lord Keśava within your heart. Maintain this concentration upon the Lord, and at the time of death you will certainly attain the supreme destination.


Although the Supreme Lord is always in the heart of every living being, the words hṛdi-sthaṁ kuru keśavam indicate that one should endeavor to realize the Lord’s presence there and maintain this awareness at every moment. Parīkṣit Mahārāja is about to give up this world and is receiving final instructions from his spiritual master, Śukadeva Gosvāmī. In the context of the King’s imminent departure, this verse has special significance.