7 There is a play here on the words mundus, the world, and mundus, clean, with its compound immundus, and its cognate verb mundare. Such plays are frequent in St. Augustine.-Tr.
15 The Greek is th\n a0rxh/n, which to some has here the sound of an adverb, like the Latin principio and primum. So at least it sounded to Chrysostom. But Augustine's interpretation is favored by Ambrose, Bernard, etc.
18 Augustine here makes Christ's speaking-His use of human language-the means whereby they should be able to know and believe Him to be the beginning, the Eternal Alpha. Had He not become man and spoken to them, but remained always hidden with the Father, and silent, they could never have had the means of knowing that He personally was the beginning, or believing Him such.-Tr.