"When a man dies all his good deeds come to an end except three: Ongoing charity (Sadaqah Jariyah), beneficial knowledge and a righteous son who prays for him."
"I came to the Messenger of Allah and said: 'My mother left a will saying that a slave should be freed on her behalf. I have a Nubian slave girl; will it suffice if I free her on her behalf?' He said: 'Bring her here.' The Prophet said to her: 'Who is your Lord?' She said: 'Allah.' He said: 'Who am I?' She said: 'The Messenger of Allah.' He said: 'Set her free , for she is a believer.'"
"O Messenger of Allah, my mother died; will it benefit her if I give in charity on her behalf?" He said: "Yes." He said: "I have a garden and I ask you to bear witness that I am giving it in charity on her behalf."
"Sa'd consulted the Messenger of Allah about a vow which his mother had to fulfill, but she died before doing so. The Messenger of Allah said: 'Fulfill it on her behalf.'"
"From Sufyan, from Az-Zuhri, from 'Ubaidullah bin 'Abdullah, from Ibn 'Abbas, that Sa'd bin 'Ubadah consulted the Prophet about a vow which his mother had to fulfill, but she died before doing so. The Messenger of Allah said: 'Fulfill it on her behalf.'"