Srimad-Bhagavatam: Canto 7 - Chapter 1 - Verse 24

Sanskrit:

आत्मन्यग्नीन् समारोप्य सन्न्यस्याहं ममात्मताम् ।कारणेषु न्यसेत् सम्यक्सङ्घातं तु यथार्हत: ॥ २४ ॥

ITRANS:

ātmany agnīn samāropyasannyasyāhaṁ mamātmatāmkāraṇeṣu nyaset samyaksaṅghātaṁ tu yathārhataḥ

Translation:

He should properly place the fire element in his own self and in this way give up bodily affinity, by which one thinks the body to be one’s self or one’s own. One should gradually merge the material body into the five elements [earth, water, fire, air and sky].

Purport:

The body is an effect of a cause, namely the five material elements (earth, water, fire, air and sky). In other words, one should know perfectly well that the material body is nothing but a combination of the five elements. This knowledge constitutes merging of the material body and the five material elements. Merging into Brahman in perfect knowledge means understanding perfectly that one is not the body but a spiritual soul.