Nedarim 18

Double trouble.

In a legal context, two sentences that run consecutively are served one after the other while two that run concurrently overlap. So for example, if you’re sentenced for two crimes, each with a sentence of three years, you might be in for six years if the sentences are consecutive. But if they run concurrently — or if you receive a pardon for just one of them — you might be in for only three.

Today’s daf concerns not double sentences, but double oaths and vows. Why might a person make the same oath or vow twice? Perhaps by error? Perhaps for emphasis? The text doesn’t say. But one thing is clear: Doubling your oath or vow has real implications — which today’s page aims to explain.

Let’s start with the mishnah from yesterday that generates today’s discussion:

There is a vow within a vow. But there is no oath within an oath. 

How so? If one said: “I am hereby a nazirite if I eat. I am hereby a nazirite if I eat,” and then he ate, he is obligated for each and every one. 

However, if he said: “I take an oath that I will not eat, I take an oath that I will not eat,” and then he ate, he is liable to bring an offering for only one violation.

One might suppose from this language that a doubly stated vow means that one has effectively made two vows, while this is not the case for a doubly stated oath, which is why one only needs to bring one offering for the latter violation. But the Gemara interprets it differently. On today’s daf, we find this teaching from Rava: 

Rava said: If he requested (dissolution) for the first, the other oath takes effect on him. From where (is this derived)? From the fact that it is not taught that there is only one. Rather, it is taught that he is liable for only one. It does not have a span (of time). When he requests (dissolution) of the other, it takes effect.

Rava focuses on the exact language of the mishnah, which specifies that someone who makes a double oath and then violates it has to bring only one offering. This implies that the person is only liable for a single violation — but not necessarily that there was only one effective oath. According to Rava, there are still, in effect, two oaths that are both valid and queued up. If someone dissolves the first, the second one slides into its place. Oaths are basically consecutive: Only one is in place at any given time.

There’s a lot more discussion and fine print. As we explore further on the page, we find that vows might actually run concurrently or consecutively. But in either case, if one of the vows is dissolved you’re still responsible for what remains.

The details are challenging, but the overall point is clear: Saying an oath or a vow twice — even if it was a mere rhetorical flourish for emphasis or an outright mistake — has real consequences. The mishnah left open the possibility that this was not always the case, but the Gemara shut that door. One way or another, the rabbis are going to hold you to both utterances.

Read all of Nedarim 18 on Sefaria.

This piece originally appeared in a My Jewish Learning Daf Yomi email newsletter sent on November 12th, 2022. If you are interested in receiving the newsletter, sign up here.

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