Wisdom behind Fajr prayer being two rak‘ahs

Question

Praise be to Allah.

Firstly:

Allah has enjoined upon His slaves five prayers to be offered each day and
night, and He has prescribed the number of rak‘ahs in each prayer according
to His wisdom and knowledge.

So we have to accept, submit and obey, and to say as the Messenger and the
believers said: “We hear, and we obey”
[al-Baqarah 2:285]. For more information, please see the answer to
question no. 65877

Secondly:

Al-Bukhaari (1090) and Muslim (685) narrated from ‘Aa’ishah, the wife of the
Prophet (blessings and peace of Allah be upon him), that she said: Prayer
was enjoined with two rak‘ahs in each prayer, whether one was staying at
home or travelling. Then the prayer when travelling was confirmed (as being
two rak‘ahs) and the prayer when not travelling was increased.

Ibn Rajab (may Allah have mercy on him) said: When Allah, may He be exalted,
enjoined upon His Messenger the five prayers each day and night, then he
came back down to earth and Jibreel (peace be upon him) led him in prayer at
the Ka‘bah, his prayer at that time was only two rak‘ahs in each prayer,
whether one was staying at home or travelling. Then the prayer when
travelling was confirmed as it was, and two rak‘ahs were added to the
prayers when staying at home. What is meant here is the four-rak‘ah prayers
only.

End quote from Fath al-Baari, by Ibn Rajab, 2/327

Ibn Khuzaymah (305) and Ibn Hibbaan (2738) narrated that ‘Aa’ishah said: The
prayers, whether travelling or staying at home were enjoined with two
rak‘ahs each, then when the Messenger of Allah (blessings and peace of Allah
be upon him) settled in Madinah, two rak‘ahs were added to the prayers when
staying at home, but Fajr prayer was left as it was, because of the length
of the recitation therein, and Maghrib prayer (was also left as it was),
because it is the Witr of the day.

Classed as hasan by Shaykh Shu ‘ayb al-Arna’oot in his commentary on
Saheeh Ibn Hibbaan.

According to a report narrated by Ahmad (26338), the first thing to be
enjoined upon the Messenger of Allah (blessings and peace of Allah be upon
him) was prayer with two rak‘ahs each, except Maghrib, which was three
rak‘ahs. Then Allah completed Zuhr, ‘Asr and ‘Isha’, making them four
rak‘ahs when staying at home, and confirming the original obligation (of two
rak‘ahs) when travelling.

Classed as hasan by the commentators on al-Musnad.

This hadith explains that when the prayer was first enjoined, it was two
rak‘ahs in each prayer, then that was confirmed in the case of travel, but
it was increased when staying at home. So Zuhr, ‘Asr and ‘Isha’ were
increased by two rak‘ahs. Fajr was confirmed as two rak‘ahs so that one
could recite at length in it. Hence the Prophet (blessings and peace of
Allah be upon him) used to recite at greater length in it than in the other
prayers. Sometimes he would recite Soorat as-Saaffaat in it when leading
them in prayer, as was narrated by Ahmad (4989) and classed as hasan by the
commentators on al-Musnad. Sometimes he recited Soorat ar-Room, as
was narrated also by Ahmad (15873) and classed as hasan by the commentators
on al-Musnad. Sometimes he recited between sixty and one hundred
verses, as is agreed upon (by the hadeeth scholars). So as to allow lengthy
recitation in Fajr prayer, it was confirmed as two rak‘ahs, as it was
enjoined in the beginning, not because two rak‘ahs were dropped from it.

Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) said:

When Allah, may He be exalted, enjoined the five daily prayers in Makkah, he
enjoined them with two rak‘ahs each. Then that was confirmed when
travelling, and more was added to the prayers when staying at home, as is
proven in as-Saheeh from ‘Aa’ishah (may Allah be pleased with her),
who said: When he (the Prophet – blessings and peace of Allah be upon him)
migrated to Madinah, (two rak‘ahs) were added to the prayers when staying at
home (i.e., not travelling); Maghrib prayer was made three rak‘ahs, because
it is the Witr of the day, and Fajr prayer was confirmed with two rak‘ahs,
so as to allow for lengthy recitation therein, hence there was no need to
increase the number of rak‘ahs.

End quote from Majmoo‘ al-Fataawa, 23/114.

A similar case is the shortening of Jumu‘ah prayer to two rak‘ahs because of
the khutbah. Ibn al-A‘raabi narrated in his Mu‘jam (1447) that
‘Aa’ishah the Mother of the Believers (may Allah be pleased with her) said:
Allah, may He be exalted, enjoined the prayer upon His Prophet (blessings
and peace of Allah be upon him) in Makkah, with two rak‘ahs in each prayer,
except Maghrib, which is the Witr of the day. When he migrated to Madinah
and settled there, two rak‘ahs were added to each two rak‘ahs, except
Maghrib prayer, for it is the Witr of the day; Fajr prayer, so as to allow
for lengthy recitation therein; and Jumu‘ah prayer, in which the prayer is
two rak‘ahs because of the khutbah.

Ibn Qudaamah (may Allah have mercy on him) said:

It was narrated from ‘Umar (may Allah be pleased with him) that he said: The
prayer was made shorter because of the khutbah. The view of ‘Aa’ishah is
similar to that. Sa‘eed ibn Jubayr said: Jumu‘ah was four (rak‘ahs), then
the khutbah took the place of two rak‘ahs. End quote from al-Mughni,
2/224

And Allah knows best.