Fulfilling another's oath

Sayyidah Aishah al-Siddiqah (may Allah be pleased with her) narrated: A woman gave her some dates placed on a platter. Sayyidah Aishah (may Allah be pleased with her) ate some of them and some were left over. The woman said: "I adjure you by an oath that you eat the rest too." The Prophet (peace and blessings be upon him) said (to Sayyidah Aishah (may Allah be pleased with her)): "Fulfil her oath for her, for the sin is upon the one who causes the oath to be broken."
Imam Ahmad recorded it, and its narrators are the narrators of the Sahih.

Sayyiduna Abu Umamah al-Bahili (may Allah be pleased with him) narrated: The Prophet (peace and blessings be upon him) was with Sayyidah Aishah (may Allah be pleased with her) when her slave-girl, or her freedwoman, came to her with some qadid (dried meat). She said: "O my mistress! Eat this, for I liked its goodness." Sayyidah Aishah (may Allah be pleased with her) said: "Keep it away from me for now." The slave-girl adjured Sayyidah Aishah (may Allah be pleased with her) by an oath. Sayyidah Aishah (may Allah be pleased with her) said: "Keep it away from me." The Prophet (peace and blessings be upon him) said: "If you make her break her oath, then its sin will be upon you."
Imam al-Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains a narrator, Ali bin Yazid, who is da'if (weak), though some have declared him thiqah (trustworthy).

Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) said: We were commanded to fulfil (other people's) oaths.
Imam al-Tabarani recorded it in al-Mu'jam al-Kabir; its chain contains a narrator, Isa bin al-Musayyab, who is da'if (weak).

Abu Hazim narrated: Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) passed by a man who had some goats with him. Sayyiduna Abdullah (may Allah be pleased with him) asked: "For how much will you sell these goats of yours? Will you sell them for such-and-such?" The man swore an oath that he would not sell them. Then Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) went on and completed his errand. When he passed by the man again, the man said: "O Abu Abd al-Rahman! Take them for the amount you were offering me." Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) said: "You swore an oath; I will not help Shaytan against you by making you break your oath."
Imam al-Tabarani recorded it in al-Mu'jam al-Kabir, and its narrators are the narrators of the Sahih.