Bhagavad Gita Chapter 10 Verse 20

Gita 10.20

अहम्, आत्मा, गुडाकेश, सर्वभूताशयस्थितः,
अहम्, आदिः, च, मध्यम्, च, भूतानाम्, अन्तः, एव, च।।20।।

Gita 10.20

Aham’, aatma, gudaakesh, sarvbhootaashaysthitH,
Aham’, aadiH, ch, madhyam’, ch, bhootaanam’, antH, ev, ch ||20||

Translation: (Gudaakesh) O Arjun! (aham’) I (sarvbhootaashaysthitH) situated in all living beings (aatma) am the soul i.e. the soul dances to the tune of Kaal, therefore this has been said (ch) and (bhootaanam’) all the living beings (aadiH) beginning (madhyam’) middle (ch) and (antH) end (ch) also (aham’) I (ev) am alone. (20)

Translation: O Arjun! I am the soul situated in all the living beings i.e. the soul dances to the tune of Kaal, therefore this has been said. And I alone am the beginning, middle and end of all the living beings.