Man Lā Yaḥḍuruh al-Faqīh
Hadith 5995569 - وَ رَوَى عَلِيُّ بْنُ مَهْزِيَارَ قَالَ : قُلْتُ لَهُ رَوَى بَعْضُ مَوَالِيكَ عَنْ آبَائِكَ عَلَيْهِمُ اَلسَّلاَمُ "أَنَّ كُلَّ وَقْفٍ إِلَى وَقْتٍ مَعْلُومٍ فَهُوَ وَاجِبٌ عَلَى اَلْوَرَثَةِ وَ كُلَّ وَقْفٍ إِلَى غَيْرِ وَقْتٍ جَهْلٌ مَجْهُولٌ بَاطِلٌ مَرْدُودٌ عَلَى اَلْوَرَثَةِ" وَ أَنْتَ أَعْلَمُ بِقَوْلِ آبَائِكَ عَلَيْكَ وَ عَلَيْهِمُ اَلسَّلاَمُ فَكَتَبَ عَلَيْهِ اَلسَّلاَمُ "هُوَ هَكَذَا عِنْدِي".
Hadith.5569 - Ali ibn Mahziyar narrated that he said: I asked Imam (as): "Some of your followers have narrated from your forefathers, peace be upon them, that every endowment (waqf) specified for a known period is binding upon the heirs, but any endowment without a specified period is unclear, invalid, and rejected by the heirs.
You (as) are more knowledgeable about the sayings of your forefathers, peace be upon them."
Imam (as) wrote in response: "It is as you have mentioned according to my understanding."