Tirmidhi

Commentary: 1؎ :
Tirmidhi has narrated this hadith in brief, while the two Shaykhs (Bukhari and Muslim) have narrated it in detail through the chain of Jarir from Mansur from Mujahid. The wording in Sahih Bukhari is as follows: He said:

I entered the mosque with Urwah bin Zubair, and Abdullah bin Umar was sitting by the chamber of Aisha,
and there were people performing the Duha prayer (Salat al-Duha) in the mosque.
He said:
We asked him about their prayer, and he said:
It is an innovation (bid‘ah).
Then he was asked:
How many ‘umrahs did the Prophet (sallallahu alayhi wa sallam) perform?
He said:
Four, one of them in Rajab.
We disliked to refute him, and then he said:
We heard the voice of Aisha, the Mother of the Believers, from the chamber, so Urwah said:
O Mother of the Believers! Do you hear what Abu Abdur-Rahman (Ibn Umar) is saying?
She said:
What is he saying?
He said:
He says that the Messenger of Allah (sallallahu alayhi wa sallam) performed four ‘umrahs, one of them in Rajab.
She said:
— May Allah have mercy on Abu Abdur-Rahman —
He did not perform any ‘umrah except that he (Ibn Umar) was present,
and he never performed ‘umrah in Rajab at all.

(Mujahid says that he and Urwah bin Zubair entered the Prophet’s Mosque and found Abdullah bin Umar (radi Allahu anhu) sitting by the chamber of Aisha (radi Allahu anha).
People were performing the Duha prayer (Salat al-Duha) in the mosque.
We asked Ibn Umar (radi Allahu anhu) about the prayer of those people,
he replied:
This is an innovation (bid‘ah).
Then Mujahid asked him: How many ‘umrahs did the Prophet (sallallahu alayhi wa sallam) perform?
He said:
Four ‘umrahs, one of them in the month of Rajab.
We disliked to refute him.
We heard the voice of Umm al-Mu’minin Aisha from the chamber, so Urwah said:
O Mother of the Believers, do you hear what Abu Abdur-Rahman Ibn Umar is saying?
She said:
What is he saying?
He said: He is saying that the Messenger of Allah (sallallahu alayhi wa sallam) performed four ‘umrahs, one of them in Rajab.
She said:
May Allah have mercy on Abu Abdur-Rahman Ibn Umar,
he was present at every ‘umrah of the Messenger of Allah (sallallahu alayhi wa sallam) (yet he is saying this),
the Prophet (sallallahu alayhi wa sallam) never performed ‘umrah in Rajab at all.)

Hadith Commentary:
Abdullah ibn al-Mubarak was from Marw.
He was a freed slave of Banu Hanzalah. He heard hadith from Hisham ibn Urwah, Imam Malik, Sufyan al-Thawri, Shu’bah, al-Awza’i, and many others besides them, and from him Sufyan ibn ‘Uyaynah, Yahya ibn Sa’id, Yahya ibn Ma’in, and others narrated. He was among those scholars who have been mentioned in the Noble Qur’an as the “Rabbani scholars.” He was the Imam of his time, a seasoned jurist (faqih), and a memorizer of hadith (hafiz al-hadith). Along with this, he was a perfect ascetic (zahid), a source of pride for his generosity, and a personification of noble character.

Isma’il ibn ‘Ayyash said that, in his time, there was no God-fearing scholar among the Muslims on the face of the earth like him.

There is no trait of goodness that Allah, exalted is He, did not bestow upon him. He also had a large number of students.

He taught hadith in Baghdad for a long period.

His year of birth is 118 AH and he passed away in 181 AH. May Allah, the Most Pure, increase his ranks in the highest gardens of Paradise (Firdaws al-Bariin) and gather us among such elders. Amin.

Alas, today the Ummah is deprived of such elders and God-fearing individuals. If only Allah, the Most Pure, would once again produce such elders and grant the Ummah the light of certainty from the knowledge of such elders.

Amin.

Hadith Commentary:
(1)
From this narration, it is understood that there is no harm in performing ‘umrah before performing hajj.
There is a detailed account of this in Musnad Ahmad:
‘Ikramah bin Khalid says:
I came to Madinah with a group of the people of Makkah, and I met ‘Abdullah bin ‘Umar (radi Allahu anhu).
I said:
We have never performed hajj; should we assume the ihram for ‘umrah from Madinah? He replied:
Yes, there is no harm in it, because the Messenger of Allah (sallallahu alayhi wa sallam) also performed ‘umrah before performing hajj.
‘Ikramah says that we assumed the ihram for ‘umrah from Madinah and completed it.
(Musnad Ahmad: 158/2) (2)
From these narrations, it is also understood that hajj had already become obligatory upon the Messenger of Allah (sallallahu alayhi wa sallam) before he performed ‘umrah.
Only in this case will the inference be correct.
(Fath al-Bari: 756/3)