Romans 2:14–15 is one of the most important of biblical texts that bear on the idea of “natural law.” I’d like over time to compile a sort of catena of Western exegesis of this passage (admittedly, the surrounding verses are important too, but I’m trying to keep it manageable). I will try to go in chronological order for the most part, though I’m not committing myself to that principle absolutely.
We begin with the so-called “Ambrosiaster,” a fourth-century commentator perhaps working in Rome in the 360s and 370s whose works were for a very long time attributed to Ambrose of Milan (hence the cipher “Ambrosiaster,” which first appears in the work of the Maurists in the seventeenth century) and who composed twelve commentaries on the letters of Paul. A set of quæstiones on the Old and New Testaments, long associated with Augustine, has also been attributed to Ambrosiaster.
The textual tradition of Ambrosiaster is, um, interesting. There are three different recensiones or versions of the Romans commentary. The text below is H. J. Vogels’ edition of “recensio gamma” (CSEL vol. 81; the others are “alpha” and “beta”), which differs from the text published by Erasmus in the sixteenth century and from that published in Patrologia Latina.
2:14: “Cum enim gentes quae legem non habent, naturaliter quae legis sunt, faciunt.” Gentes Christianos dicit, quia magister gentium est, sicut dicit alio loco: “Vobis enim dico gentibus,” qui incircumcisi neque neomenias, neque sabbatum, neque escarum legem servant et duce natura credunt in deum et Christum, id est in Patrem et Filium. Hoc est enim legem servare, deum legis agnoscere. Prima enim sapientiae pars haec est: timere deum patrem, ex quo sunt omnia, et dominum Iesum filium eius, per quem sunt omnia. Ipsa ergo natura proprio iudicio creatorem suum agnoscit, non per legem, sed per rationem naturae; opus enim opificem cernit in se.
2:15: “Hi legem non habentes, ipsi sibi sunt lex, qui ostendunt opus legis scriptum in cordibus suis.” Idem sensus est, quia dum natura duce credunt, opus legis ostendunt non per litteram, sed per conscientiam. Opus enim legis fides est, quam cum dictis dei exhibet, naturali iudicio ostendit semetipsum legem sibi esse, quia quod mandat lex, ultro facit, ut credat in Christum.
“Testimonium reddente conscientia illorum.” Teste interiore conscientia sua credunt, quia conscii sibi sunt convenire sibi, quod credunt; congruum est enim creaturae credere et venerari suum Conditorem: nec absurdum est, ut dominum servus agnoscat.
2:14: “For when the Gentiles who do not have the law by nature (naturaliter) do the things that belong to the law.” He refers to Christians as Gentiles, because he is the teacher of the Gentiles, as he says in another place: “For I speak to you Gentiles,” who, as those who are uncircumcised, do not keep new moons, nor the sabbath, nor food laws, and with nature as guide (duce natura) believe in God and Christ, that is, in the Father and the Son; for this is what it is to keep the law: to recognize the God of the law. For the first part of wisdom is this: to fear God the Father, from whom are all things, and the Lord Jesus his Son, through whom are all things. Therefore nature itself (ipsa natura) recognizes by its own judgment (proprio iudicio) its own Creator, not through the law, but through the reason of nature (per rationem naturæ); for the work (opus) discerns the workman (opificem) in itself.
2:15: “These, not having the law, themselves are a law to themselves, who display the work of the law written in their hearts.” The sense is the same; because, while they believe with nature as guide (natura duce), they display the work of the law not through the letter (non per litteram), but through conscience (per conscientiam). Moreover, the work of the law is faith; and when [sc. “the conscience”? or “a person”?] exhibits it (i.e., faith) in the words of God, by natural judgment (naturali iudicio) it shows that it itself is a law to itself, because that which the law commands it does voluntarily, [namely,] to believe in Christ.
“With their conscience rendering testimony.” With their conscience as interior witness (teste interiori) they believe, because they are conscious (conscii) with themselves that it is appropriate for them to believe; for it is appropriate for a creature to believe in and to worship its Creator; nor is it absurd that a servant recognize his master.1