In plain words
One is the Self, abiding as the Self, and yet one asks of oneself, 'Who am I? What is the place where I abide?' Say that such a one is no different from the drunkard who says, 'Who am I? In what place am I?'
Word for word
Though being oneself, as oneself, of oneself asking 'Who am I? What is the place in which I abide?': to such a one, say, he is equal to the drinker of liquor who says 'Who am I? In what place am I?'