Death brings an end to one’s ability to perform good deeds and it is a long journey that requires enough provisions and only three qualities can make this journey easier. Allah’s Messenger (sallallahu alaihi wa-sallam) said: “When a man dies all his good deeds end, except for three cases; the charity of continuous blessings, beneficial knowledge that he left behind and a righteous child who prays for him.[Saheeh Muslim (vol. 3, p.867, no. 4005)]

Allah’s Messenger (sallallahu alaihi wa-sallam) explained how a child can benefit his parents after their death. Narrated Abu Usayd Malik ibn Rabiah as-Saidi: “While we were with the Messenger of Allah (sallallahu alaihi wa-sallam), a man of Banu Salmah came to him and said: ‘O Messenger of Allah, is there any kindness left that I can do to my parents after their death?’ He replied: “Yes, there are four qualities to perform:-
 
1. Pray (to Allah to grant them mercy) and invoke (Him) to forgive them,
2. Fulfill their promises (or will),
3. Be generous to their friends,
4. Keep relations with the kindred, which you are kindred through your parents. This is what remains of the kindness that you could perform towards them after they die.” [Sunan of Abu-Dawood (5123)]
Note: The last wishes (wasiyah or will) expressed by the person should be fulfilled so long as they are in accordance with the Sharee’ah.

Performing Hajj on behalf of the Dead:
Another form of worship known from the Sunnah that can be performed on behalf of the dead is Hajj (Pilgrimage). Hajj can only be performed on behalf of the dead after completing one’s obligation of performing Hajj. It was narrated from Ibn Abbas that the Messenger of Allah (sallallahu alaihi wa-sallam) heard a man saying “Labbayka ‘an Shubrumah (At your service, O Allah, on behalf of Shubrumah).” The Messenger of Allah (sallallahu alaihi wa-sallam) asked: “Who is Shubrumah?” He said, “A relative of mine.” The Prophet (sallallahu alaihi wa-sallam) said, “Have you ever done Hajj before?” He replied: “No.” Allah’s Messenger (sallallahu alaihi wa-sallam) ordered him, “Do this Hajj for yourself, then do Hajj on behalf of Shubrumah.” [Abu Dawood (1811). The hadeeth is classed as Saheeh by Shaikh al-Albanee in Irwaa’ al-Ghaleel (4/171)]

Charity on behalf of the Deceased Parents:
Charity given on behalf of the deceased will benefit them and its reward will reach him, according to the consensus of the Muslims. Abu Hurayrah narrated that a man said to the Prophet (sallallahu alaihi wa-sallam): “My father has died and left behind wealth, and he did not make a will. Will it be expiation for him if I give in charity on his behalf?” He said, “Yes.” [Saheeh Muslim (1630)]

Aa’ishah (radhi allahu anha) also narrated that a man said to the Prophet (sallallahu alaihi wa-sallam): “My mother died suddenly and I think that if she could have spoken she would have given in charity [i.e., left instructions that some of her estate be given in charity]. Will I have a reward if I spend in charity on her behalf?” He said, “Yes.” [Saheeh Muslim (1004)]

Imam An-Nawawi (rahimahullah) said: “This Hadeeth indicates that it is permissible to give in charity on behalf of the deceased and that doing so is Mustahabb (recommended), and that the reward for that will reach the deceased and benefit him or her; it will also benefit the one who gives the charity. There is consensus on all of that among the Muslims.”

Duties of the Child towards his dead Parents:
1) Making up their obligatory fasts: Aa’isha (radhi allahu anha) narrated that the Messenger of Allah (sallallahu alaihi wa-sallam) said: “Whoever dies and had any fasts outstanding, his heir should observe those fasts on his behalf.” [Saheeh al-Bukharee (1851) and Saheeh Muslim (1147)]
A woman came to Allah’s Messenger (sallallahu alaihi wa-sallam) asking: “My mother has died and she had one month’s fasting outstanding.” He (sallallahu alaihi wa-sallam) said, “Do you not think that if she was in debt, you would pay it off for her?” She said, “Yes” He (sallallahu alaihi wa-sallam) said: “The debt owed to Allah is more deserving of being paid off.” [Saheeh al-Bukharee (1817) and Saheeh Muslim (1148)]

2) Fulfilling their vows of worship and Paying off their debts: It was reported from Ibn Abbas (radhi allahu anhu) that a woman from Juhaynah came to the Prophet (sallallahu alaihi wa-sallam) and said: “My mother vowed to go for Hajj, but she did not go for Hajj before she died. Should I do Hajj on her behalf?” He said, “Yes, do Hajj on her behalf. Do you not think that if your mother was in debt you would pay it off for her? Pay off the debt that is owed to Allah, for Allah is more deserving that what is owed to Him should be paid off.” [Saheeh al-Bukharee (1754)]

3) Maintaining ties with those whom they used to keep in touch with from relatives and friends. Allah’s Messenger (sallallahu alaihi wa-sallam) said: “The best of righteous deeds is for a man to keep in touch with his father’s friends after he dies.” [Saheeh Muslim (2552)]

When Abdullah Ibn Umar (radhi allahu anhu) set out to Makkah, he kept a donkey with him to ride when he would get tired from riding of the camel, and had a turban which he tied around his head. One day, as he was riding the donkey, a bedouin happened to pass by him. He (Abdullah Ibn Umar) said: “Aren’t you so and so?” The bedouin said: “Yes.” He (Abdullah Ibn Umar) gave him the donkey and his turban and said: “Ride this donkey, and tie this turban around your head.” Some of his companions said: “May Allah forgive you, you gave to this bedouin the donkey which you enjoyed to ride for change, and the turban which you tied around your head.” Abdullah Ibn Umar (radhi allahu anhu) said: “I heard the Messenger of Allah (sallallahu alaihi wa-sallam) saying, “The finest act of goodness is the kind treatment of a person to the loved ones of his father after his death,” and the father of this person was a friend of Umar (radhi allahu anhu).” [Saheeh Muslim]