In plain words
Eternal, with no gap anywhere in it, the real Brahman: look again and again, saying 'I am That' (so'ham). Whoever contemplates the one, day after day, and stands without wavering, becomes the supreme Brahman, filled with the nature of deathlessness.
Word for word
Frequently recognise ‘I am That’, eternal undivided Brahman. Whoever continually contemplates the one and stands unwavering abides as supreme Brahman, filled with deathlessness.