In this Ayah, Allah the Exalted affirms His favor, generosity, graciousness, compassion and beneficence towards His creation. When the offspring of the righteous believers imitate their parents regarding faith, Allah will elevate the latter to the ranks of the former, even though the latter did not perform deeds as goodly as their parents. Allah will comfort the eyes of the parents by seeing their offspring elevated to their grades. Surely, Allah will gather them together in the best manner, and He will not decrease the reward or the grades of those higher in rank for joining them together, hence His statement,

﴿أَلْحَقْنَا بِهِمْ ذُرِّيَّتَهُمْ وَمَآ أَلَتْنَـهُمْ مِّنْ عَمَلِهِم مِّن شَىْءٍ﴾

(to them shall We join their offspring, and We shall not decrease the reward of their deeds in anything.) Ath-Thawri reported that Ibn `Abbas said, "Verily, Allah elevates the ranks of the believers' offspring to rank of their parents, even though the latter have not performed as well as the former, so that the eyes of the parents are comforted.'' Ibn `Abbas then recited this Ayah,

﴿وَالَّذِينَ ءَامَنُواْ وَاتَّبَعَتْهُمْ ذُرِّيَّتُهُم بِإِيمَـنٍ أَلْحَقْنَا بِهِمْ ذُرِّيَّتَهُمْ وَمَآ أَلَتْنَـهُمْ مِّنْ عَمَلِهِم مِّن شَىْءٍ﴾

(And those who believe and whose offspring follow them in faith, -- to them shall We join their offspring, and We shall not decrease the reward of their deeds in anything.) Ibn Jarir and Ibn Abi Hatim recorded this statement from Sufyan Ath-Thawri from Ibn `Abbas. Ibn Abi Hatim also recorded that Ibn `Abbas commented on Allah's statement,

﴿وَالَّذِينَ ءَامَنُواْ وَاتَّبَعَتْهُمْ ذُرِّيَّتُهُم بِإِيمَـنٍ أَلْحَقْنَا بِهِمْ ذُرِّيَّتَهُمْ﴾

(And those who believe and whose offspring follow them in faith, -- to them shall We join their offspring.) saying, "They are the offspring of the believers who died on the faith. If the ranks of their parents are higher than their ranks, they will be joined with their parents. No part of the reward their parents received for their good deeds will be reduced for them.'' `Abdullah, son of Imam Ahmad, recorded that `Ali said, "Khadijah asked the Prophet about two of her children who died during the time of Jahiliyyah, and the Messenger of Allah said;

«هُمَا فِي النَّار»

(They are both in the Fire.) When he saw sadness on her face, he said,

«لَوْ رَأَيْتِ مَكَانَهُمَا لَأَبْغَضْتِهِمَا»

(If you saw their dwelling place, you would hate them.) She said, `O Allah's Messenger! What about my children with you.' He said,

«فِي الْجَنَّة»

(They are in Paradise.) The Messenger of Allah said,

«إِنَّ الْمُؤْمِنِينَ وَأَوْلَادَهُمْ فِي الْجَنَّةِ، وَإِنَّ الْمُشْرِكِينَ وَأَوْلَادَهُمْ فِي النَّار»

(Verily, the believers and their offspring will dwell in Paradise, while the idolators and their offspring will dwell in the Hellfire.) The Prophet then recited the Ayah,

﴿وَالَّذِينَ ءَامَنُواْ وَاتَّبَعَتْهُمْ ذُرِّيَّتُهُم بِإِيمَـنٍ﴾

(And those who believe and whose offspring follow them in faith...)'' Certainly, it is Allah's grace and favor that He grants the children this blessing because of the good deeds of their parents. He also grants His favor to parents on account of their offspring invoking Allah for them. Imam Ahmad recorded that Abu Hurayrah, may Allah be pleased with him, said that the Messenger of Allah said,

«إِنَّ اللهَ لَيَرْفَعُ الدَّرَجَةَ لِلْعَبْدِ الصَّالِحِ فِي الْجَنَّةِ فَيَقُولُ: يَا رَبِّ أَنْى لِي هذِهِ؟ فَيَقُولُ: بِاسْتِغْفَارِ وَلَدِكَ لَك»

(Verily, Allah shall elevate the grade of a righteous servant in Paradise, who will ask, "O Lord! How did I earn this'' Allah will reply, "Through your son's invoking Me to forgive you.'') This Hadith has an authentic chain of narration, but it was not recorded in the Sahih this way. However, there is a witnessing narration for it in Sahih Muslim, from the Hadith of Abu Hurayrah, who said that the Messenger of Allah said,

«إِذَا مَاتَ ابْنُ آدَمَ انْقَطَعَ عَمَلُهُ إِلَّا مِنْ ثَلَاثٍ: صَدَقَةٍ جَارِيَةٍ، أَوْ عِلْمٍ يُنْتَفَعُ بِهِ، أَوْ وَلَدٍ صَالِحٍ يَدْعُو لَه»

(When the Son of Adam dies, his record of deeds will cease except in three cases: an ongoing charity, knowledge that people are benefiting from and a righteous son who invokes Allah for him.)