In plain words
It is not the breath of life, prāṇa, nor the breath that moves down, apāna, nor in the same way the inner faculty above them. It is what knows everything, whole and complete, the Self. Come to it, contemplating it always.
Word for word
The Self is not prana or apana, nor the faculty beyond them. Always contemplate the all-complete Self that knows all, and attain it.