Hazrat Saeed bin Musayyib and Hasan, regarding a person who joins a congregation thinking it is Zuhr prayer while the people are actually offering Asr prayer, state that he should repeat both prayers.

Hasan says that if a traveler forgets a prayer during travel and remembers it while at home, he should perform the travel prayer; and if he forgets a prayer at home and remembers it during travel, he should perform the home prayer.

Ibrahim also says the same.

Hasan says that if a person forgets a prayer while at home (not traveling) and remembers it during a journey, he should offer the prayer as it is performed at home. And if he forgets a prayer during a journey and remembers it at home, he should offer the prayer as it is performed during a journey.

Hazrat Sufyan says that he will offer the same prayer which he had forgotten.

Hazrat Hammad says that if a person forgets to offer a prayer while at home (not traveling) and remembers it during a journey, he should offer four rak‘ahs. And if he forgets to offer a prayer during a journey and remembers it at home, he should offer the prayer of the journey.

Hazrat Abdullah bin Masood (may Allah be pleased with him) narrates that the polytheists kept the Noble Prophet (peace and blessings be upon him) occupied with four prayers during the Battle of Badr. When a large part of the night had passed, the Noble Prophet (peace and blessings be upon him) ordered Hazrat Bilal to give the call to prayer. He gave the call to prayer and pronounced the iqamah, then the Prophet first performed the Zuhr prayer, then pronounced the iqamah and performed the Asr prayer, then pronounced the iqamah and performed the Maghrib prayer, then pronounced the iqamah and performed the Isha prayer.

Hazrat Abu Saeed narrates that during the Battle of Khandaq, we were unable to perform the Zuhr, Asr, Maghrib, and Isha prayers. Until Allah the Exalted revealed this verse { وَکَفَی اللَّہُ الْمُؤْمِنِینَ الْقِتَالَ وَکَانَ اللَّہُ قَوِیًّا عَزِیزًا }. Then the Holy Prophet (peace and blessings be upon him) stood up and instructed Hazrat Bilal, who gave the call for the prayer. Then he performed the Zuhr prayer as he used to perform it before. Then the call for Asr was given and he performed the Asr prayer as he used to perform it before. Then he performed the Maghrib prayer as he used to perform it before. Then the call for Isha was given and he performed the Isha prayer as he used to perform it before. This action was before the revelation of this verse { فَإِنْ خِفْتُمْ فَرِجَالاً أَوْ رُکْبَانًا }.

Hazrat Umar says that if a person has a habit of reciting (the Qur'an) at night and is unable to do so, then he should do it before Zuhr; in this way, it is as if he has performed this act at night.

Hazrat Abu Bakr bin Amr narrates that a man sought permission to meet Hazrat Umar at noon. He did not grant him permission for quite some time. Then, he was granted permission. Hazrat Umar said to him, "I used to recite a portion of the Holy Qur'an at night, but I could not recite it last night, so I am reciting it at this time."