Abu Sa’eed al-Khudri (May Allah be pleased with him) said:-
“Whoever reads Surah al-Kahf on the night of Jumu’ah, will have a light that will stretch between him and the Ancient House (the Ka’bah).”
(Narrated by al-Daarimi# 3407. This hadeeth was classed as saheeh by Shaykh al-Albaani in Saheeh al-Jaami, 6471)
“Whoever reads Surah Al-Kahf on the day of Jumu’ah, will have a light that will shine from him from one Friday to the next.”
(Narrated by al-Haakim, 2/399; al-Bayhaqi, 3/249. It was classed as saheeh by Shaykh al-Albaani in Saheeh al-Jaami’, 6470)
Note:-The surah may be read during the night or the day of Jumu’ah. The night of Jumu’ah starts from sunset on Thursday, and the day of Jumu’ah ends at sunset. Therefore the time for reading this surah extends from sunset on Thursday to sunset on Friday.
Narrated by Jaabir ibn ‘Abdillah (may Allah be pleased with him) who said:
The Messenger of Allah (صلى الله عليه وسلم) said:
“The day of Friday has twelve hours, in which there is no Muslim slave who asks Allah for anything but He will grant it to him, so seek it in the last hour after ‘Asr.”
Reported by Abu Dawood (1048) and an-Nasaa’i (1389); classed as saheeh by al-Albaani in Saheeh Abi Dawood; and by an-Nawawi in al-Majmoo‘, 4/471
Here is an excerpt from Ibnul Qayyim (rahimahullaah):
There is an hour of acceptance, and it is the hour in which no Muslim happens to supplicate to Allah for something except that it will be given to him. In the hadeeth reported by al-Bukharee and Muslim on the authority of Abu Hurayrah that Allaah’s Messenger (salallaahu ‘alayhi wa sallam) said:
Indeed, there is an hour (opportune time) on Friday and if a Muslim gets it while praying and asks something from Allah, then Allah will definitely meet his demand. And he (salallaahu ‘alayhi wa sallam) pointed out the shortness of that time with his hands.
Translated by brother Salah al-Iranee