Bukhari

Hadith Commentary:
In the narration of Al-Hakim, it is reported from Anas (radi Allahu anhu) that when the Prophet (sallallahu alayhi wa sallam) approached near Madinah, the young girls of Banu Najjar came out beating the duff and singing. They were saying:
نحن جوار من بني نجار
یا حبذا محمد من جار
In another narration, it is mentioned that the girls of the Ansar came out singing and beating the duff in joy at your arrival.
They were saying:
طلع البدر علينا من ثنیات الوداع
وجب الشکرعلینا ما دعا للہ داع
The Prophet (sallallahu alayhi wa sallam) said:
“Indeed, Allah loves you,” meaning: know that Allah, the Exalted, loves you.
Qastallani has also presented the names of those twenty Companions (radi Allahu anhum) who had migrated and reached Madinah before the Prophet (sallallahu alayhi wa sallam).
The “Mufassalat” surahs are those which begin from Surah Al-Hujurat.

Hadith Commentary:
1.
The Messenger of Allah (sallallahu alayhi wa sallam) instructed Mus‘ab ibn ‘Umayr (radi Allahu anhu) to migrate and entrusted him with the position of teacher and preacher in Madinah Tayyibah.
When the Messenger of Allah (sallallahu alayhi wa sallam) arrived, he stayed at the house of Kulthum ibn Hidm (radi Allahu anhu).
Some narrations indicate that he stayed with Sa‘d ibn Khaythamah (radi Allahu anhu).
In reality, Sa‘d was unmarried.
His house was called "Bayt al-‘Uzzab," meaning the house of the unmarried.
The Messenger of Allah (sallallahu alayhi wa sallam) took up permanent residence at the house of Kulthum (radi Allahu anhu) and would also sit with his noble Companions (radi Allahu anhum) at the house of Sa‘d ibn Khaythamah (radi Allahu anhu). When ‘Ali (radi Allahu anhu) learned that the Messenger of Allah (sallallahu alayhi wa sallam) was safely residing in Quba’, he too came to Quba’ after him.
(‘Umdat al-Qari: 11/646)
It is narrated from Anas (radi Allahu anhu) that when the Messenger of Allah (sallallahu alayhi wa sallam) approached Madinah, the young girls of Banu Najjar came out beating their tambourines and reciting these verses:
“We are the girls of the tribe of Najjar; how fortunate we are to have the neighborhood of the Messenger of Allah (sallallahu alayhi wa sallam)!” In another narration, it is mentioned that, in joy at the arrival of the Messenger of Allah (sallallahu alayhi wa sallam), the girls of the Ansar were singing this verse:
“From the valleys of Wada‘, the full moon has risen upon us; gratitude to Allah is incumbent upon us as long as a caller calls to Allah.” The chain of this last narration is connected. The correct and preferred view is that these verses were recited upon return from the Battle of Tabuk.
(Fath al-Bari: 7/327)
2.
In this hadith, “Mufassal” refers to all the surahs from Surah al-Hujurat to the end (of the Qur’an).
They are called “Mufassal” because after each surah, the repetition of separation by “Bismillah” occurs.
There are three categories of these:
“Long Mufassal” (Tiwal al-Mufassal): from Surah al-Hujurat to Surah al-Buruj.
“Middle Mufassal” (Awsat al-Mufassal): from Surah al-Buruj to Surah al-Bayyinah.
“And Short Mufassal” (Qisar al-Mufassal): from Surah al-Bayyinah to the last surah, an-Nas.

Hadith Commentary:
➊
In the first verse of this surah, there is a command for the glorification (tasbih) of Allah, the Exalted.
What is meant by this is that His Essence is free from every kind of defect and imperfection.
He alone, without any partner, is the Absolute Controller over everything; He has complete control over all things in the universe. To perform tasbih means to remember Allah, the Exalted, with these mentioned attributes.

➋
When this verse was revealed, the Messenger of Allah (sallallahu alayhi wa sallam) said:
“In accordance with this verse, recite (Subhana Rabbiyal A‘la) in prostration (sujud),
and in accordance with the last verse of Surah Al-Waqi‘ah, recite (Subhana Rabbiyal ‘Azim) in bowing (ruku‘).”
(Musnad Ahmad: 4/155)