2,742. A Vow Whose Meaning Is Unclear

Hilchos Nedarim 2:6

The Rambam says that some Geonim maintain that the conditions described in the previous halachos only apply to vows, not to oaths, though he cites a divergent opinion who maintains that these laws apply to both vows and oaths. Accordingly, one may make a condition to cancel an oath the same as one may do with a vow.

Hilchos Nedarim 2:7

If someone makes a vow and his intention is unclear, we act stringently. If he explains his meaning, there’s room to act both leniently and stringently, as follows: If one says that produce should be to him like salted meat and wine poured as a libation, we ask him what he meant. If he says that he intended sacrifices and wine poured on the altar, the produce is prohibited to him; if he says that he meant the sacrifices and libations of idols, the produce remains permitted. If he made the vow without having a specific meaning in mind, the produce is prohibited to him.