। ॥
In plain words
In the centre of the cave of the Heart, Brahman alone shines, directly, as the Self, as 'I, I'. Enter the Heart with a mind that searches for itself or dives within, or by restraining the movement of the breath, and abide in the Self.
Word for word
In the middle of the Heart's cave, Brahman alone shines directly as the Self, as 'I, I'. Enter the Heart with a mind searching for oneself or diving, or by stopping the movement of breath; become one established in the Self.