53. Moreover the surpassing excellence of the nature of the Spirit is to be learned not only from His having the same title as the Father and the Son, and sharing in their operations, but also from His being, like the Father and the Son, unapproachable in thought. For what our Lord says of the Father as being above and beyond human conception, and what He says of the Son, this same language He uses also of the Holy Ghost. "O righteous Father," He says, "the world hath not known Thee," meaning here by the world not the complex whole compounded of heaven and earth, but this life of ours subject to death, and exposed to innumerable vicissitudes. And when discoursing of Himself He says, "Yet a little while and the world seeth me no more, but ye see me;" again in this passage, applying the word world to those who being bound down by this material and carnal life, and beholding the truth by material sight alone, were ordained, through their unbelief in the resurrection, to see our Lord no more with the eyes of the heart. And He said the same concerning the Spirit. "The Spirit of truth," He says, "whom the world cannot receive, because it seeth Him not, neither knoweth Him: but ye know Him, for He dwelleth with you." For the carnal man, who has never trained his mind to contemplation, but rather keeps it buried deep in lust of the flesh, as in mud, is powerless to look up to the spiritual light of the truth. And so the world, that is life enslaved by the affections of the flesh, can no more receive the grace of the Spirit than a weak eye the light of a sunbeam. But the Lord, who by His teaching bore witness to purity of life, gives to His disciples the power of now beth beholding and contemplating the Spirit. For "now," He says, "Ye are clean through the word which I have spoken unto you," wherefore "the world cannot receive Him, because it seeth Him not, ... but ye know Him; for he dwelleth with you." And so says Isaiah;--"He that spread forth the earth and that which cometh out of it; he that giveth breath unto the people upon it, and Spirit to them that trample on it" ; for they that trample clown earthly things and rise above them are borne witness to as worthy of the gift of the Holy Ghost. What then ought to be thought of Him whom the world cannot receive, and Whom saints alone can contemplate through pureness of heart? What kind of honours can be deemed adequate to Him?