Bg 9.19

tapamy aham aham varsam
nigrhnamy utsrjami ca
amrtam caiva mrtyus ca
sad asac caham arjuna

Word for word: 
tapami — give heat; aham — I; aham — I; varsam — rain; nigrhnami — withhold; utsrjami — send forth; ca — and; amrtam — immortality; ca — and; eva — certainly; mrtyuh — death; ca — and; sat — spirit; asat — matter; ca — and; aham — I; arjuna — O Arjuna.

Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
O Arjuna, I give heat, and I withhold and send forth the rain. I am immortality, and I am also death personified. Both spirit and matter are in Me.

Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Krishna, by His different energies, diffuses heat and light through the agency of electricity and the sun. During the summer season it is Krishna who checks rain from falling from the sky, and then during the rainy season He gives unceasing torrents of rain. The energy which sustains us by prolonging the duration of our life is Krishna, and Krishna meets us at the end as death. By analyzing all these different energies of Krishna, one can ascertain that for Krishna there is no distinction between matter and spirit, or, in other words, He is both matter and spirit. In the advanced stage of Krishna consciousness, one therefore makes no such distinctions. He sees only Krishna in everything.

Since Krishna is both matter and spirit, the gigantic universal form comprising all material manifestations is also Krishna, and His pastimes in Vrndavana as two-handed Syamasundara, playing on a flute, are those of the Supreme Personality of Godhead.