Collected chapters on the grandfather -- Chapter: The inheritance of the grandfather

Sayyiduna Imran bin Husayn (may Allah be pleased with him) said that a man came to the Messenger of Allah (peace and blessings be upon him) and said: My son's son has died; what inheritance is there for me? He (peace and blessings be upon him) said: "You get a sixth." When he turned to leave, he (peace and blessings be upon him) called him back and said: "You get another sixth." When he turned to leave, he (peace and blessings be upon him) called him back and said: "The other sixth is a provision (tu'mah)."

Sayyiduna Ma'qil bin Yasar (may Allah be pleased with him) said that Sayyiduna Umar (may Allah be pleased with him) asked the people: "Does anyone know anything from the Messenger of Allah (peace and blessings be upon him) concerning the grandfather?" Sayyiduna Ma'qil (may Allah be pleased with him) said: "He (peace and blessings be upon him) gave him a sixth." Sayyiduna Umar (may Allah be pleased with him) asked: "Along with whom, woe to you?" Sayyiduna Ma'qil (may Allah be pleased with him) said: "I do not know." Sayyiduna Umar (may Allah be pleased with him) said: "May you never know!"
In one narration, Amr bin Maymun (may Allah have mercy on him) said: I performed Hajj with Sayyiduna Umar (may Allah be pleased with him). Sayyiduna Umar (may Allah be pleased with him) called out to the people: "Has anyone heard anything from the Messenger of Allah (peace and blessings be upon him) concerning the grandfather?" Sayyiduna Ma'qil bin Yasar (may Allah be pleased with him) stood up and said: "I heard the Messenger of Allah (peace and blessings be upon him); an inheritance case in which there was a grandfather was brought to him, and he (peace and blessings be upon him) gave him a sixth or a third." Sayyiduna Umar (may Allah be pleased with him) asked: "What was the case?" Sayyiduna Ma'qil (may Allah be pleased with him) said: "I do not know." Sayyiduna Umar (may Allah be pleased with him) struck him (lightly) and said: "May you never know! What prevented you from knowing?"

Kharijah bin Zayd narrates from his father (may Allah be pleased with him) that the inheritance of the grandfather is this: he does not inherit anything along with the father; with a male child and with a son's son he is entitled to a sixth; and apart from that, as long as the deceased does not leave a paternal half-brother or half-sister, the grandfather takes the father's place. The shares of those entitled to fixed shares are given first; then, if the remaining property is more than a sixth, it is given to the grandfather, and if it is not more than a sixth, a sixth is given to the grandfather.
(40) Chapter: The severity regarding speaking without ijtihad on the issue of the grandfather with full brothers and paternal half-brothers, and the disagreement about it

Sayyiduna Ibn Umar (may Allah be pleased with them both) said: I heard Sayyiduna Umar (may Allah be pleased with him) on the pulpit of the Messenger of Allah (peace and blessings be upon him) saying: Amma ba'd (to proceed)! O people, the prohibition of wine has been revealed, and it is made from five things: grapes, dates, honey, wheat and barley; and wine (khamr) is whatever clouds the mind. And there are three matters about which I wished that he (peace and blessings be upon him) had told us the ruling before parting from us: kalalah, the grandfather, and the rulings of usury (riba).

Abidah (may Allah have mercy on him) said: I have memorised from Sayyiduna Umar (may Allah be pleased with him) a hundred rulings concerning the grandfather, each of them differing from the others.

Muhammad (bin Sirin) narrates from Abidah, who said: I memorised from Sayyiduna Umar (may Allah be pleased with him) a hundred rulings concerning the grandfather. And he (Umar) said: I have given various rulings concerning the grandfather, and in all of them I spared no effort to reach the truth. If I live until the summer, if Allah wills, I will give a ruling on it so clear that even a woman could judge by it while sitting on the hem of her garment.

Tariq bin Shihab (may Allah have mercy on him) said: Sayyiduna Umar (may Allah be pleased with him) took a shoulder blade (to write on) and gathered the Companions of Muhammad (peace and blessings be upon him) in order to write (a ruling on) the grandfather, and they thought that he would make him (equal to) a father. Then a snake came out at him and they dispersed. He said: "If Allah had wanted to carry it through, He would have carried it through."

Amr bin Maymun (may Allah have mercy on him) said: I went to Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) when he had been stabbed. Sayyiduna Umar (may Allah be pleased with him) said: "O Abdullah, bring me the shoulder blade on which I wrote the matter of the grandfather yesterday." And he said: "If Allah had wanted to complete this matter, He would have completed it." Sayyiduna Abdullah (may Allah be pleased with him) said: "O Commander of the Faithful, we will spare you this matter." Sayyiduna Umar (may Allah be pleased with him) said: "No." Then he took it and erased it with his hand.

Sa'id bin Jubayr narrates from a man of (the tribe of) Murad that he heard Sayyiduna Ali (may Allah be pleased with him) saying: "Whoever would be pleased to plunge into the pits of Hell, let him judge between the grandfather and the brothers."