Creating Light

Et dixit Deus: Fiat lux et facta est lux.   Congruit operibus Dei ut mundi ornatum a luce incipiat, cum ipse sit lux vera, lucemque habitet inaccessibilem; cujus beatissima visione mox creati in coelis coelorum angeli jam perfrui coeperant. Apte huic quoque saeculo ornado primam materialis gratiam lucis donavit, ut esset unde caetera quae crearet apparerent. Quod autem dixisse Deus, sive ut lux fieret, sive alia quaeque perhibetur, non nostri more per sonum vocis corporeum fecisse credendus est, sed altius intelligendum dixisse Deum ut fieret creatura, quia per Verbum suum omnia, id est, per unigenitum Filium fecit. De quo manifestius evangelista Joannes: In principio, inquit, erat Verbum, et Verbum erat apud Deum, et Deus erat Verbum. Hoc erat in principio apud Deum; omnia per ipsum facta sunt. Quod ergo ait, omnia facta per Verbum Dei Joannes, hoc est, quod Moyses ait, quia dixit Deus, Fiat lux; dixit, Fiat firmamentum; dixit, Fiat caetera creatura. Hoc quod psalmus adjuncta et Spiritus sancti persona dicit: Verbo Domini coeli firmati sunt, et Spiritu oris ejus omnis virtus eorum. Rabanus Maurus, Commentariorum In Genesim Libri Quatour, Liber I Migne PL 107 447-8

'And God said let there be light and there was light.' 1 It befits the works of God that He begins the ornamentation of the world with light, when He is the true light and dwells in light inaccessible, 2 which with blessed vision the recently created angels of heaven in heaven have already begun to enjoy. Fittingly also concerning this adornment of the world does He give the first grace of material light, that the other things which are to be created appear. And as God spoke, whether 'Let there be light', or whatever other thing He was to bring forth, He should not be thought to have created in a manner like ours, through some sound of the corporeal voice, but it should be thought that in a higher sense God brought creatures into being, because through the Word, the Only begotten Son, He made all things. Concerning which it is made plain in the Gospel of John when he says, 'In the beginning was the Word and the Word was with God and God was the Word. In the beginning He was with God and through Him all things were made.' 3 Thus John said that everything was made through the Word of God, that is, as Moses said that God spoke, 'Let there be light' and 'Let the firmament be,'  and so on with the other created things He made. And a Psalm adds the person of the Holy Spirit, saying: 'With the Word of the Lord the heavens are made firm and with the Spirit of His mouth every power of them.' 4 Rabanus Maurus, from the Commentary On Genesis, Book I 1 Gen 1.3 21 Tim 6.16 3 Jn 1.1-3 4 Ps 32.6