”O you who believe! When you are told to make room in the assemblies, (spread out and) make room…”
Allaah (The Most High) said:
يَا أَيُّهَا الَّذِينَ آمَنُوا إِذَا قِيلَ لَكُمْ تَفَسَّحُوا فِي الْمَجَالِسِ فَافْسَحُوا يَفْسَحِ اللَّهُ لَكُمْ ۖ وَإِذَا قِيلَ انْشُزُوا فَانْشُزُوا يَرْفَعِ اللَّهُ الَّذِينَ آمَنُوا مِنْكُمْ وَالَّذِينَ أُوتُوا الْعِلْمَ دَرَجَاتٍ ۚ وَاللَّهُ بِمَا تَعْمَلُونَ خَبِيرٌ
”O you who believe! When you are told to make room in the assemblies, (spread out and) make room. Allah will give you (ample) room (from His Mercy). And when you are told to rise up, rise up. Allah will exalt in degree those of you who believe, and those who have been granted knowledge. And Allah is Well-Acquainted with what you do.” [58:11]
This is a practical code of behaviour commanded by Allaah to His believing slaves that when they come together in one of their gatherings, then some of them or some who have already arrived need to make room (for others); for indeed it is from (good) etiquettes to make room for him (i.e. the other person) to reach this goal. And this is not to harm the one (already) in the gathering in anyway—so he enables his (Muslim) brother to reach his goal without him being harmed, and reward is given in accordance with the performed action; for indeed whoever makes room, Allaah makes room for him, and whoever shows generosity to his brother, Allaah will show him generosity.
[وَإِذَا قِيلَ انْشُزُوا – And when you are told to rise up]; Meaning: Rise up and retire from your gathering for an (obligatory or important) need (i.e. prayer etc), then [فَانْشُزُوا ] ”rise up;” That is: Embark upon the fulfilment of that beneficial affair—for indeed the fulfilment of the likes of these affairs is related to knowledge and Eemaan; and Allaah (The Most High) will exalt in degree the people of knowledge and Eemaan in accordance with what Allaah has specified for them of knowledge and Eemaan.
[وَاللَّهُ بِمَا تَعْمَلُونَ خَبِير -And Allah is Well-Acquainted with what you do]; Meaning: So that Allaah [The Most High] rewards every performer of deeds in accordance with his deeds—if they are good, there is good recompense for it, and if they are evil deeds, there is an evil recompense for it. And in this Ayah [i.e. 58:11] is (a manifestation) of the virtue of knowledge and that its beautification and fruit is to discipline (oneself) with its etiquettes and act in accordance with what it necessitates.
[For further details, see Tayseer Al-Kareem Ar-Rahmaan Fee Tafseer Kalaam Al-Mannaan]