Subject Matter of the Narrative:
According to Tirmidi’s narrative no. 718, it is reported that the Prophet (pbuh) said:
إذا كان على الميت نذر صيام يصوم عنه وإذا كان عليه قضاء رمضان أطعم عنه.
‘When upon a deceased is an unfulfilled pledge to fast, [the person responsible for him should] fast on his behalf and when upon a deceased is to fast for the month of Ramadan, [the person responsible for him should] feed on his behalf.’
Comment on the Narrative
This narrative has been categorized as weak (i.e., Da`eef) by Al-albaniy.
In view of Al-albaniy’s comment on the chain of the narrtive, it does not seem prudent to safely hold this narrative as one which can reliably be ascribed to the Prophet (pbuh).
(This write-up is prepared by the Hadith Cell of Javed Ahmad Ghamidi)
 See: Al-albaniy’s “Da`eef Sunan al-Tirmidi”, narrative no. 718.