Sanskrit
तपाम्यहमहं वर्षं निगृह्णाम्युत्सृजामि च । अमृतं चैव मृत्युश्च सदसच्चाहमर्जुन ॥
tapāmy aham ahaṃ varṣaṃ nigṛhṇāmy utsṛjāmi ca amṛtaṃ caiva mṛtyuś ca sad asac cāham arjuna
Translation
I give heat; I hold back and send forth the rain; immortality and also death, being and non-being am I, Arjuna.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
Closes the four-verse identification run by claiming the most fundamental opposites of all — heat and rain, immortality and death, being and non-being (sat and asat). Ending the sequence on “being and non-being” is a deliberate escalation: having claimed every particular thing in verses 16-18, this verse claims the categories underneath particularity itself.