Al-Kāfi - The Book of Wills

Chapter: The Owner is more Rightful to his Property as Long as he is Living َيْدُ بْنُ زِيَادٍ عَنِ الْحَسَنِ بْنِ ٠َاعَةَ عَنِ ابْنِ أَبِي عُ٠َّارٍ السَّابَاطِيِّ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلا٠َيِّتُ أَحَقُّ بِ٠َ فِيهِ الرُّوحُ يُبِينُ بِهِ قَالَ نَعَ٠ْ فَإِنْ أَوْصَى بِهِ فَإِنْ تَعَدَّى فَلَيْسَ لَهُ إِلا الثُّلُثُ.

He (the Imam) said, ‘Yes, that is right but if he makes a will and it is more (than the one-third) it applies to one-third of his legacy only.”’ وثق - Allamah Baqir al-Majlisi (Mirʾāt al-ʿUqūl fī Sharḥ Akhbār Āl al-Rasūl (23/16))