Tafsir of As-Sajdah 32:17

فﻼ تعلم نفس ما أخفي لهم من قرة أعين

No person knows what is kept hidden for them of delights of eyes, means, no one knows the vastness of what Allah has concealed for them of everlasting joy in Paradise and delights such as no one has ever seen. Because they conceal their good deeds, Allah conceals the reward for them, a fitting reward which will suit their deeds. Al-Hasan Al-Basri said, "If people conceal their good deeds, Allah will conceal for them what no eye has seen and what has never crossed the mind of man." It was recorded by Ibn Abi Hatim. Al-Bukhari quoted the Ayah:

فﻼ تعلم نفس ما أخفي لهم من قرة أعين

(No person knows what is kept hidden for them of delights of eyes), then he recorded that Abu Hurayrah, may Allah be pleased with him, said that the Messenger of Allah said:

قال الله تعالى

أعددت لعبادي الصالحين ما ﻻ عين رأت وﻻ أذن سمعت وﻻ خطر على قلب بشر

Allah says: "I have prepared for My righteous servants what no eye has seen, no ear has heard, and it has never crossed the mind of man.'' Abu Hurayrah said: "Recite, if you wish:

فﻼ تعلم نفس ما أخفي لهم من قرة أعين

(No person knows what is kept hidden for them of delights of eyes). It was also recorded by Muslim and At-Tirmidhi. At-Tirmidhi said, "It is Hasan Sahih.'' In another version of Al-Bukhari:

وﻻ خطر على قلب بشر ذخرا من بله ما أطلعتم عليه

"and no body has ever even imagined of. All that is reserved, besides which, all that you have seen is nothing.'' It was also reported from Abu Hurayrah, may Allah be pleased with him, that the Prophet said:

من يدخل الجنة ينعم ﻻ يبٲس ﻻ تبلى ثيابه وﻻ يفنى شبابه في الجنة ما ﻻ عين رأت وﻻ أذن سمعت وﻻ خطر على قلب بشر

Whoever enters Paradise, will enjoy a life of luxury and never feel deprivation, his clothes will never wear out, his youth will never fade. In Paradise there is what no eye has ever seen, no ear has ever heard, and has never crossed the mind of man. This was recorded by Muslim.

جزاء بما كانوا يعملون

as a reward for what they used to do