। ॥ १८ ॥
In plain words
Brahman is defined as satyam—reality, jñānam—pure knowing, and anantam—without limit. You are real; Jñāna—pure knowing—is your very nature; you are without limit. Therefore Brahman is you alone.
Close to the Sanskrit
Reality, Jñāna—knowledge—and infinitude are said to be the defining marks of Brahman. Because you are real, of the nature of Jñāna, and infinite, it is indeed you alone.