Bismillah-Hirrahman-Nirrahim
Hadith: Agar koi Namaz parhna bhul jaye to jab bhi yaad aaye usko parh le
Anas bin Malik Radi-Allahu-Anhu se rivayat hai ki Rasoollallah Sallallhu-Alaihi-Wasallam ne farmaya agar koi Namaz parhna bhul jaye to jab bhi yaad aaye usko parh le , is Qadha ke siwa aur koi kaffara uska nahi hai
Sahih Bukhari, Vol1, 597
Jaber bin Abdullah Radi-Allahu-Anhu se rivayat hai ki Hazrat Umar bin Khattab Radi-Allahu-Anhu gazwa-e-khandaq ke moqey par suraj ghurub honey ke baad aaye aur wo kufaar e quraish ko bura bhala kahney lagey phir aapney farmaya oh Allah ke Rasool Sallallhu-Alaihi-Wasallam suraj ghurub ho gaya aur Asar ki Namaz parhna mere liye mumkin na ho saka is par Rasoollallah Sallallhu-Alaihi-Wasallam ne farmaya mainey bhi Namaz nahi parhi hai phir hum Wadi-e-bathan mein gaye aur wahan aapney namaz ke liye wudhu kiya humney bhi wudhu banaya us waqy suraj dub chuka tha , pahley Aap Sallallhu-Alaihi-Wasallam ne Asar ki Namaz parhayee phir maghrib ki namaz parhayee
Sahih Bukhari, Vol 1, 596
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Narrated Anas Radi-Allahu-Anhu The Prophet Sallallhu-Alaihi-Wasallam said, "If anyone forgets a prayer he should pray that prayer when he remembers it. There is no expiation except to pray the same."
Sahih Bukhari, Vol 1, Book 10, No. 571
Narrated Jabir bin 'Abdullah Radi-Allahu-Anhu On the day of Al-Khandaq (the battle of trench.) 'Umar bin Al-Khattab came cursing the disbelievers of Quraish after the sun had set and said, "O Allah's Apostle I could not offer the 'Asr prayer till the sun had set." The Prophet said, "By Allah! I, too, have not prayed." So we turned towards Buthan, and the Prophet performed ablution and we too performed ablution and offered the 'Asr prayer after the sun had set, and then he offered the Maghrib prayer.
Sahih Bukhari, Volume 1, Book 10, Number 570