Bhagavad Gita Chapter 11, Text 18

Bg 11.18

tvam aksaram paramam veditavyam
tvam asya visvasya param nidhanam
tvam avyayah sasvata-dharma-gopta
sanatanas tvam puruso mato me

Word for word: 
tvam — You; aksaram — the infallible; paramam — supreme; veditavyam — to be understood; tvam — You; asya — of this; visvasya — universe; param — supreme; nidhanam — basis; tvam — You; avyayah — inexhaustible; sasvata-dharma-gopta — maintainer of the eternal religion; sanatanah — eternal; tvam — You; purusah — the Supreme Personality; matah me — this is my opinion.

Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
You are the supreme primal objective. You are the ultimate resting place of all this universe. You are inexhaustible, and You are the oldest. You are the maintainer of the eternal religion, the Personality of Godhead. This is my opinion.