Ibn Majah

Benefit:
It is understood from this that after the obligatory Friday prayer, two units (rak‘ahs) of Sunnah may also be performed, and four units as well. Some have reconciled between these two by stating that if one performs them in the mosque, then he should perform four Sunnah (either in sets of two with separate salutations, or with one salutation for all four), and if he performs them after going home, then he should perform two units. (Mir‘aat)

1427. Commentary: There is no mention in the hadith of performing the prayer in the mosque. In reality, Imam al-Nasa’i rahimahullah is reconciling between the narrations, because in one narration there is mention of the Messenger of Allah sallallahu alayhi wa sallam performing two units (rak‘ah) of prayer. See: [صحیح البخاري ، الجمعة ، حدیث : 937 ، و صحیح مسلم ، الجمعة ، حدیث 882]. The author rahimahullah has specified the narration of four units for the mosque, and the narration of two units for the home, because in that narration the home is mentioned—that is, if one prays after coming home, then two units, and if one prays in the mosque, then four units. However, the preferred opinion is that both two and four units may be performed. And Allah knows best. Whereas some people are of the view that both the verbal and practical narrations should be acted upon—that is, one should perform four and also two, making a total of six units—but this view is without evidence.

1131. Commentary:
This instruction is for encouragement and recommendation.

Benefit:
From this hadith, it is established that four rak‘ahs should be performed after the Jumu‘ah prayer, and performing two rak‘ahs is also permissible (Sahih al-Bukhari: 895). Whatever is possible should be performed. It is preferable to offer voluntary (nafl) prayers at home.