This view—that praying four units is disliked—is the most balanced of the positions. It is the position Ahmad explicitly stated in al-Athram’s report. When asked whether a traveller may pray four units, he replied, “I do not favour it; rather, prayer during travel is two units.”
Al-Marwadhī also reported that he said, “If he wishes, he may pray four units, and if he wishes, he may pray two.” Ahmad’s statements consistently hold that shortening the prayer is preferable. Indeed, it is reported that he hesitated to affirm that praying four units discharges the obligation.
Mālik’s position is that praying four units is disliked and that the prayer should be repeated within its prescribed time. Hence, two views are mentioned within his school concerning whether a four-unit prayer is valid. Al-Shāfi‘ī’s position permits either course. There are two views concerning which is preferable; the sounder is that shortening the prayer is preferable, as in one of the two reports from Ahmad. This is also the position chosen by many of his followers.
Ahmad’s hesitation to affirm that it discharges the obligation implies that a ruling on the matter is to be derived from his statements within his school. At most, the person has made a disliked addition, and this does not invalidate the prayer: he has performed what is obligatory and something extra. An addition made out of forgetfulness does not invalidate the prayer, by the agreement of the Muslims. The same applies to an addition made in error, in the belief that it is permissible. Such an addition is not made by someone who believes it forbidden, but only by someone who believes it permissible. There is no explicit text declaring it forbidden. Rather, the evidence indicates that it is contrary to the Sunnah, not that it is forbidden—like praying without raising the hands, turning to look around during prayer, and similar disliked acts. We shall discuss this matter fully, Allah willing.
As for ‘Uthmān’s praying the full prayer, his conduct should be understood in light of what he used to say