O King, give up the animalistic mentality of thinking, “I am going to die.” Unlike the body, you have not taken birth. There was not a time in the past when you did not exist, and you are not about to be destroyed.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
त्वं तु राजन् मरिष्येति पशुबुद्धिमिमां जहि । न जातः प्रागभूतोऽद्य देहवत्त्वं न नङ्क्ष्यसि
tvaṃ tu rājan mariṣyeti paśubuddhimimāṃ jahi | na jātaḥ prāgabhūto'dya dehavattvaṃ na naṅkṣyasi
SB 12.5.2