There are saheeh ahaadeeth from the Prophet (peace and blessings of
Allaah be upon him) concerning the virtues of reciting Soorat al-Kahf
during the day or night of Jumu’ah (Friday). These include:
(a) From Abu Sa’eed al-Khudri, who said: “Whoever
reads Soorat 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)
(b) “Whoever reads Soorat 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. Ibn Hajar said in Takhreej
al-Adhkaar that this is a hasan hadeeth, and he said, this is the
strongest report that has been narrated concerning reading Soorat
al-Kahf. See: Fayd al-Qadeer, 6/198. It was classed as saheeh by Shaykh
al-Albaani in Saheeh al-Jaami’, 6470)
The soorah 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 soorah extends from
sunset on Thursday to sunset on Friday.
Al-Mannaawi said:
Al-Haafiz ibn Hajar said in his Amaali: “In
some reports it says ‘the day of Jumu’ah’ and in some reports it says
‘the night of Jumu’ah’. They may be reconciled by saying that what is
meant is the day which includes the night and vice versa.” (Fayd al-Qadeer, 6/199)
Al-Mannaawi also said:
“It is recommended to read it during the day or night of Jumu’ah, as al-Shaafa'i (may Allaah have mercy on him) stated.” (Fayd al-Qadeer, 6/198)