so someone who does not know that a day is part of Ramadan cannot conceivably form a definite intention to fast it as part of Ramadan.

Shortening prayers while travelling and combining two prayers may also come under this heading. The established Sunnah of the Messenger of Allah, may Allah bless him and grant him peace, was to shorten prayers when travelling: he would perform every four-unit prayer as only two units. The two senior Companions who succeeded him, Abū Bakr and then ‘Umar, did likewise. He would combine two prayers while travelling only occasionally, when needed. His combining was unlike his shortening: shortening was his regular practice, whereas combining was an occasional concession.

Anyone who reports that the Prophet, may Allah bless him and grant him peace, performed the noon, afternoon or night prayer as four units while travelling is mistaken. No one has transmitted this from him through any chain of transmission, whether authentic or weak. Some people, however, have narrated a hadith from ‘Ā’ishah, in which she said:

“When travelling, the Messenger of Allah, may Allah bless him and grant him peace, would shorten his prayers while I performed them in full, and he would refrain from fasting while I fasted. I asked him about this, and he said, ‘You have done well, ‘Ā’ishah.’”

Some scholars mistakenly understood this to mean that he himself would sometimes shorten his prayers while travelling and sometimes perform them in full. No one has narrated that. Moreover, the very hadith reporting her conduct is false. Neither ‘Ā’ishah nor anyone else accompanying the Prophet, may Allah bless him and grant him peace, prayed otherwise than as he prayed. No one ever prayed four units with him, whether at ‘Arafah, Muzdalifah or elsewhere, whether they were residents of Mecca or anyone else. Rather, all the Muslims would pray two units with him. During his stay at Minā in the days of the pilgrimage season, he would lead the people in prayers of two units, as did Abū Bakr after him, then ‘Umar