, 18: Life of Severus Alexander
51.7-8 (tr. David Magie):
He used often to exclaim what he had heard from someone, either a Jew or a Christian, and always remembered, and he also had it announced by a herald whenever he was disciplining anyone, "What you do not wish that a man should do to you, do not do to him." And so highly did he value this sentiment that he had it written up in the Palace and in public buildings.
clamabatque saepius, quod a quibusdam sive Iudaeis sive Christianis audierat et tenebat, idque per praeconem, cum aliquem emendaret, dici iubebat, "quod tibi fieri non vis, alteri ne feceris." quam sententiam usque adeo dilexit ut et in Palatio et in publicis operibus praescribi iuberet.
praescribi Hermann Peter: perscribi PΣ
Mentioned by Albrecht Dihle, Die Goldene Regel: Eine Einführung in die Geschichte der antiken und frühchristlichen Vulgärethik
(Göttingen: Vandenhoeck & Ruprecht, 1962), p. 10.