तपाम्यहमहं वर्षं निगृह्णाम्युत्सृजामि च। अमृतं चैव मृत्युश्च सदसच्चाहमर्जुन ॥

tapāmyaham ahaṁ varṣhaṁ nigṛihṇāmyutsṛijāmi cha amṛitaṁ chaiva mṛityuśh cha sad asach chāham arjuna

I give heat; I hold back and send forth the rain; immortality and also death, being and non-being am I, Arjuna.

In plain words: Krishna tells Arjuna that he gives heat, and he holds back the rain or lets it fall. He is both immortality and death, both what exists and what does not.