The intercession of the righteous

Sayyiduna Abu Umamah (may Allah be pleased with him) says: I heard the Prophet (peace and blessings be upon him) say: "Through the intercession of one man who will not be a prophet, people as numerous as the two tribes of Rabi'ah and Mudar will enter Paradise." A man said: "O Messenger of Allah, is Rabi'ah not a part of Mudar?" The Prophet (peace and blessings be upon him) said: "It is just as I have said."
Ahmad and al-Tabarani recorded it with various chains. The narrators of Ahmad, and the narrators of one of al-Tabarani's chains, are the narrators of the Sahih, except Abd al-Rahman bin Maysarah, and he is thiqah (trustworthy).

Sayyiduna Abu Barzah (may Allah be pleased with him) says: I heard the Prophet (peace and blessings be upon him) say: "There will be a person in my Ummah who will intercede for more people than Rabi'ah and Mudar, and there will be a person belonging to my Ummah who will be enlarged in Hell until he becomes one of its corners."
Ahmad recorded it, and its narrators are thiqat (trustworthy).

Sayyiduna Abu Umamah (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) said: "Through the intercession of one man from my Ummah, more people than the number of the tribe of Mudar will enter Paradise. A man will intercede for the people of his household, and a man will intercede according to the measure of his deeds."
Al-Tabarani recorded it, and its narrators are the narrators of the Sahih, except Abu Ghalib; more than one scholar declared him trustworthy, and there is weakness in him.

Sayyiduna Anas (may Allah be pleased with him) narrates this saying of the Prophet (peace and blessings be upon him): "On the Day of Resurrection, the people of Hell will be presented in rows. The believers will pass by them, and a man from the people of Hell will see a man from the believers whom he knew in the world, and will say: 'O so-and-so, do you remember? On such a day you sought my help in such-and-such a matter.' The Prophet (peace and blessings be upon him) said: 'Then the believer will remember that, he will recognise him, and he will intercede for him before his Lord, and his intercession for that man will be accepted.'"
Abu Ya'la recorded it, and al-Tabarani in al-Mu'jam al-Awsat; its chain contains a narrator, Yusuf bin Khalid al-Samti, and he is a kadhdhab (liar).

Sayyiduna Anas bin Malik (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) said: "(On the Day of Resurrection) a man will intercede for two or three people."
Al-Bazzar recorded it, and its narrators are the narrators of the Sahih.

Sayyiduna Anas (may Allah be pleased with him) narrates this saying of the Prophet (peace and blessings be upon him): "Two men were passing through a wilderness; one of them was a worshipper and the other was a sinner. The worshipper felt such severe thirst that he collapsed. His companion looked at him; the companion had a water-skin with some water in it, and he kept looking at him as he lay fallen. He thought: 'By Allah, if this righteous man dies of thirst while I have water, I will never receive any good from Allah Almighty; but if I give him my water to drink, I will die.' He put his trust in Allah Almighty, made a firm resolve, sprinkled some of his water on him (the worshipper) and gave him the rest to drink. The worshipper stood up and crossed the wilderness. The Prophet (peace and blessings be upon him) said: On the Day of Resurrection that sinner will be made to stand for the reckoning, and then he will be ordered to be taken to Hell. The angels will set off with him. He will see the worshipper and say: 'O so-and-so, do you recognise me?' He will ask: 'Who are you?' He will reply: 'I am so-and-so, who preferred you over myself on the occasion of crossing the wilderness.' He will say: 'Yes, I have recognised you.' Then he will say to the angels: 'Wait!' And he will stop there. He (the worshipper) will come, stand and begin to supplicate to his Lord, saying: 'O my Lord, You know the favour he did me and how he preferred me over himself. O my Lord, grant him to me!' The Lord will say: 'He is yours!' The Prophet (peace and blessings be upon him) said: Then the worshipper will come, take that man by the hand and admit him into Paradise.
Abu Ya'la recorded it, and its narrators are the narrators of the Sahih, except Abu Zilal al-Qasmali; Ibn Hibban and others declared him trustworthy, and more than one scholar declared him da'if (weak).

Sayyiduna Anas (may Allah be pleased with him) narrates that the Prophet (peace and blessings be upon him) said: "A man from the people of Paradise will look down upon the people of Hell, and a man from the people of Hell will call out to him: 'O so-and-so, do you recognise me?' The man of Paradise will say: 'No, by Allah, I do not recognise you. Who are you? Woe to you!' He will say: 'I am the man who passed by you in the world, and you asked me for water to drink and I gave you a drink; because of that, intercede for me before your Lord!' The Prophet (peace and blessings be upon him) said: That (man of Paradise) will present himself before his Lord, where other people will also be present, and will say: 'O Lord, I looked down upon the people of Hell, and a man from the people of Hell stood up and called out: "O so-and-so, do you not recognise me?" I said: "No, by Allah, I did not recognise you. Who are you?" He said: "I am the man by whom you passed in the world, and you asked me for a drink and I gave you a drink, so now because of that intercede for me before your Lord." So, O my Lord, accept my intercession for him!' The Prophet (peace and blessings be upon him) said: Then Allah Almighty will accept his (the man of Paradise's) intercession for him (the man of Hell) and will bring him out of Hell."
Abu Ya'la recorded it; its chain contains a narrator, Abu Ali bin Abi Sarah, and he is matruk (abandoned).