Bhagwad Gita
Chapter 10, Verse 20
अहमात्मा गुडाकेश सर्वभूताशयस्थितः।
अहमादिश्च मध्यं च भूतानामन्त एव च।।10.20।।
I am the Self, O Gudakesa, seated in the hearts of all creatures. I am the beginning, the middle and the end of all beings.