BG 10.20
अहमात्मा गुडाकेश सर्वभूताशयस्थितः। अहमादिश्च मध्यं च भूतानामन्त एव च
aham ātmā guḍākeśha sarva-bhūtāśhaya-sthitaḥ aham ādiśh cha madhyaṁ cha bhūtānām anta eva cha
O Arjuna! I am the Self, seated in the hearts of all beings; I am the beginning, the life, and the end of them all.
Translated by Shri Purohit Swami
I am the Self, O Gudakesa, seated in the hearts of all beings; I am the beginning, the middle, and the end of all beings.
Translated by Swami Sivananda
Word meanings (from the gita/gita dataset)
aham—I; ātmā—soul; guḍākeśha—Arjun, the conqueror of sleep; sarva-bhūta—of all living entities; āśhaya-sthitaḥ—seated in the heart; aham—I; ādiḥ—the beginning; cha—and; madhyam—middle; cha—and; bhūtānām—of all beings; antaḥ—end; eva—even; cha—also