This is necessary lest you say: Although the one who took the vow stood in judgment before he died and the court obligated him, since the object of his vow was not assessed before he died, the property of the one who vowed is not liened to the debt, and consequently the heirs are not obligated to pay. Therefore, the Mishnah teaches us that the property of the one who took the vow was liened, since he stood in judgment while he was still alive, and the assessment of the object of the vow is considered to be a mere disclosure of the matter, which can be performed after the death of the one who vowed.
מתני׳ ״שור זה עולה״, ו״בית זה קרבן״, ומת השור ונפל הבית — פטור מלשלם. ״שור זה עלי עולה״, ו״בית זה עלי קרבן״, מת השור ונפל הבית — חייב לשלם.
Mishnah: In the case of one who says: This bull is consecrated as a burnt offering, or: This house is consecrated as an offering, and the bull died or the house collapsed, he is exempt from paying his commitment. But in the case of one who says: It is incumbent upon me to give this bull as a burnt offering, or: It is incumbent upon me to give this house as an offering, if the bull died or the house collapsed, he is obligated to pay its value.
גמ׳ אמר רבי חייא בר רב: לא שנו אלא דאמר ״דמי שור זה עלי עולה״, אבל אמר ״שור זה עלי עולה״, כיון דאמר ״זה״ ומת — אינו חייב באחריותו, ״עלי להביאו״ קאמר.
Talmud: R' Ḥiyya bar Rav says: A baraita states in the Mishnah only that one who said: It is incumbent upon me to give the monetary value of this bull as a burnt offering, is obligated to pay its value if it dies. But if he said: It is incumbent upon me to give this bull as a burnt offering, since he said: This, thereby referring specifically to that animal, and then the bull died, he does not bear financial responsibility for its loss. And as for his statement: It is incumbent upon me, he did not intend to accept financial responsibility for the loss of the bull. Rather, he meant to say: It is incumbent upon me to bring this bull as an offering to the Temple.