There are actually two somewhat related issues here that need pinning down. In addition to the definition of “law,” there is the overall textual question as to whether this verse even belongs in I Corinthians in the first place. And if the anwer to this question is “no,” then the meaning of “law” is a moot point. I must apologize for the following discussion since it tends to move back and forth in discussing these two items.
The NRSV places all of 14:34b-36 in parentheses, for reasons explained by Richard A. Horsley: “Since these statements silencing women in the assembly are found in two different places in the ancient manuscripts, between 14:33 and 14:36 and after 14:40, they may be a marginal gloss later interpolated into the text; similar wording occurs in 1 Tim 2:11-12...”
One certainly does not have to agree with all of Horsley's reasoning here in order to take his last comment as a good hint in helping us answer the subject question about the law. Especially since Towner goes even further regarding that final comment by pointing to four close parallels between the I Corinthians and I Timothy passages.
Thus, if we turn to I Timothy 2, we read in verses 12-14: “I permit no woman (or wife) to teach or have authority over a man; she is to keep silent. For Adam was formed first, then Eve; and Adam was not deceived, but the woman was deceived and became a transgressor.”
We see here in I Timothy that the passage Paul quotes to prove his point is not really a law in the sense of the laws in Leviticus, but instead is a narrative example found in Genesis, one of “the five books of the law” called the Pentateuch. As to which specific passage (or passages) Paul is citing, Towner says, “the supporting material alludes to and draws together two parts of the Genesis story, three if v. 15a is also allusive: (1) the story of the creation of Adam and Eve (2:13; Gen 2:7-8,15), (2) the story of Eve's temptation (2:14; Gen 3:6-13), and (3) the pronouncement of judgment on the woman as a result of her role in the event (2:15a; Gen 3:16).”
Similarly, Knight states that 'the law' in I Corinthians 14:34 and the Genesis 2-3 passages alluded to in I Timothy are the same.
Adding to this supposition that Paul has a broader definition of “the law” in I Corinthians is the fact that the Old Testament itself appears to be known as “the law” in I Corinthians 9:8 and 14:21. The first of these passages refers specifically to Deuteronomy 25:4 while the quotation in the second passage actually comes from Isaiah 28:11-12.
J. Murray writes in The New Bible Dictionary, pp. 721-723, “There is much flexibility in the use of the term 'law' (nomos) in the New Testament.” He enumerates these various meanings as follows:
1. All or part of the Old Testament writings, especially the five books of Moses
2. The Mosaic administration dispensed at Mt. Sinai
3. An expression of God's will in general
4. A word of God specially revealed to particular recipients
5. A negative expression about those who are still following the OT regulations
6. A general operating or governing principle of life
So according to the above, it is possible that in I Corinthians 14 Paul may be using any of those definitions with the probable exception of #5. First, let me mention one minority opinion on what Paul must mean in I Corinthians.
As D.A. Carson explains in his book Exegetical Fallacies, 2nd ed., pp. 38-40, “Walter C. Kaiser, Jr., has argued more than once that nomos in 1 Corinthians 14:34-35 refers not to Mosaic law but to rabbinic interpretation, rabbinic rules that Paul has come to reject.” Carson replies: “This interpretation has its attractions, but it will not stand up to close scrutiny...there is no need for such a procedure of last resort. The passage can be and has been adequately explained in its context. There are ample parallels to this way of looking to the Old Testament for a principle, not a quotation (and the principle in question is doubtless Gen. 2:20b-24, referred to by Paul in both 1 Cor. 11:8-9 and in 1 Tim. 2:13)...”
But David K. Lowery states, “Gen. 3:16 [is] the text Paul probably referred to in 1 Cor. 14:34.” (The Bible Knowledge Commentary: New Testament)
H. Esser (DNTT, 2, p. 446) says that “in 1 Cor 14:34 he [i.e. Paul] refers to Gen. 3:16 to support his command that women be silent in the church, a command which is probably not meant to apply generally, but specifically to speaking with tongues....” Other scholars particularize Paul's words as applying only to the Corinthian situation at that time period, to married women, or to a prolonged dialogue or argument between the teacher and a woman pupil.
“The reference to the law probably has in mind Gen 3:16.” (W.F. Orr and J.A. Walther, I Corinthians, Anchor Bible)
“Paul's omission of the words 'to their husbands' is significant since it serves to emphasize the dependent position of women in general. A command of this nature is found in the law (Gen. 3:16).” (F.W. Grosheide, First Epistle to Corinthians, NICNT)
“Given Paul's understanding of man and woman from 'the law' (v. 34, alluding to Gen 2:18-25), the subordinate position of the woman is inconsistent with her 'weighing' a man's prophecies.” (R.C. Ortlund, Jr., New Dictionary of Biblical Theology, p. 654)
And finally, a dissenting view from the evangelical scholar Gordon Fee from his massive commentary on I Corinthians in Eerdman's New International Commentary on the New Testament series. Fee, who goes to great lengths to prove that verses 34-37 are not authentically Pauline in authorship, says this regarding “the law” in v. 34: “Real problems for Pauline authorship lie with the phrase 'even as the Law says.' First, when Paul elsewhere appeals to 'the Law,' he always cites the text (e.g. 9:8; 14:21), usually to support a point he himself is making. Nowhere else does he appeal to the Law in this absolute way as binding on Christian behavior. More difficult yet is the fact that the Law does not say any such thing. Gen. 3:16 is often appealed to, but that text does not say what is here argued. If that were the case, then one must admit that Paul is appealing not to the written Torah itself but to an oral understanding of Torah such as found in rabbinic Judaism...under any view this is difficult to reconcile with Paul. Some (e.g. Martin) have argued that 'law' here does not mean the Torah, but simply 'principle' or 'rule,' thus referring to Paul's earlier instruction. But in an unqualified form that lacks Pauline precedent.”
Assuming that I Timothy 2:13 is a valid parallel to Paul's writing in I Corinthians 14:34-35, we can next add the comments of some scholars on the Pastoral Epistles:
A.T. Hanson: “Both the more ancient Targums on Gen. 3:16 interpret the verse so as to mean that because of her sin the woman is to be totally subordinate to her husband for good or evil, and to find that her God-given vocation. This would not at all accord with Paul's view of salvation.”
Thomas D. Lea and Hayne P. Griffin, Jr.: “The chronological priority of Adam becomes the support of Paul's command that the women were to show a spirit of attentiveness to hearing and were to avoid an attempt at domineering men.”
Donald Guthrie: “In Cor. xi.9, Paul had already made use of the argument that the priority of man's creation places him in a position of superiority over woman, the assumption being that the original creation, with the Creator's own imprimatur upon it, must set a precedent for determining the true order of the sexes. Their relationship, as Simpson points out, was 'not competitive, but concordant and counterpart.'”
Ronald A. Ward concludes v. 13 to be “a biblical foundation for a practical policy. The woman was chronologically later than the man; physically dependent on him; and mentally oriented to him (Gen. 1:27; 2:7,22; 1 Cor. 11:8f.).”
So at this point, it is fair to say that, assuming the I Corinthians passage is authentically Pauline, the “law” he cites is, broadly speaking, found in the narrative of Genesis 1-3 though scholars may disagree on which exact verses are primarily in mind. Thus, it meets Murray's Definition #3 quoted earlier, although that does not exclude the possibility that Paul received a special revelation from God regarding the underlying meaning of that OT passage (Definition #4) or derived it from personal reflection on Genesis 1-3 (Definition #6).
But that brings us back to the question as to whether I Corinthians 14:34-35 (or as in NRSV, all of vv. 33b-36) is truly Pauline in the first place. Regarding this minority opinion voiced primarily by Gordon Fee, one of his arguments against the authenticity of these verses is that the vocabulary found there differs from that employed by Paul in his other writings. However, that claim does not really stand up to scrutiny. Consider the following:
“silence” (oigato) appears in both I Corinthians 14:28 and 14:34.
“learn” (manthanosin) occurs in I Corinthians 14:31 and 14:34.
“come to” (katanntao) is found in I Corinthians 10:11 and 14:36.
Perhaps another telling fact is that “husband” appears exactly 12 times (a common biblical number symbolic of relationships) in I Corinthians 14, but only if 14:35 is included.
Then, consider the two following phrases:
“a shame for a woman to” is utilized in both I Corinthians 11:6 and 14:35.
“at home” occurs in I Corinthians 11:34 and 14:35.
The above verbal coincidences are well beyond the realm of possibility of occurring if 14:34-37 came from a different hand than the rest of I Corinthians.
Finally, I will turn to the writings of two textual experts who have both written notable commentaries on the text of the Greek New Testament. Regarding I Corinthians 14:34-35, they write:
“Some MSS...place these verses after 14:40, prompting some scholars to deem these verses as a gloss that was added into the text...But the earliest MSS...place the verses after 14:33.” (John Wesley Comfort)
And Bruce M. Metzger labels these textual variants as scribal “attempts to find a more appropriate location in context for Paul's directive concerning women.”
The final conclusion from all the above is that there is a reasonably strong consensus that (1) I Corinthians 14:34-36 is a genuine Pauline passage which belongs in its current position in the text, and (2) “the law” he refers to encompasses the main events of Genesis 2-3.