42. For although most authorities read “de Spiritu,” yet the Greek from which the Latins translated have “ἐχ πνεύματος ἁγίου,” that is, “ex Spiritu Sancto.” For that which is “of” [ex] any one is either of his substance or of his power. Of his substance, as the Son, Who says: “I came forth of the Mouth of the Most High;” Ecclus. xxiv. 3. as the Spirit, “Who proceedeth from the Father;” S. John xv. 20. of Whom the Son says: “He shall glorify Me, for He shall receive of Mine.” S. John xvi. 14. But of the power, as in the passage: “One God the Father, of Whom are all things.” 1 Cor. viii. 6. The argument from the exact force of prepositions is often urged by the Fathers, as by St. Athanasius and St. Basil among the Greeks. The Latins also use it, as St. Ambrose here, but occasionally the same Greek prepositions are variously rendered, which destroys the force of the argument. With regard to the two prepositions ex and de St. Augustine gives a very good explanation, De Natura Bon, c. 27: “Ex ipso [of Him] does not always mean the same as de ipso [from Him]. That which is from Him can be said to be of Him, but not everything which is of Him is rightly said to be from Him. Of Him are the heavens and the earth, for He made them, but not from Him, because not of His substance.” But neither the Vulgate nor even St. Ambrose himself is quite consistent in this matter.