An Important Etiquette: [Make Room For Others In The Gatherings And Sittings So That Allaah Will Give You Ample Room From His Mercy]
In The Name of Allaah, The Most Merciful, The Bestower of Mercy
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, some of them or some of those who have already arrived should make room [for others]; for indeed it is from [good] etiquettes to make room for him [i.e. the other person] to reach his goal. And this is not to harm the one who is [already] in the gathering in anyway; rather he enables his [Muslim] brother to reach his goal without him being harmed, and reward is given in accordance with a deed; 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: To rise up and retire from your gathering for an [obligatory or important] need [i.e. prayer etc], then [فَانْشُزُوا – rise up] – Meaning: proceed towards the fulfilment of that beneficial affair, for indeed the fulfilment of the likes of these affairs is connected to knowledge and Eemaan. And Allaah [The Most High] will exalt in degree the people of knowledge and Eemaan in accordance with what He has portioned out for them from knowledge and Eemaan.
[وَاللَّهُ بِمَا تَعْمَلُونَ خَبِير -And Allah is Well-Acquainted with what you do]- Meaning: Allaah [The Most High] rewards every performer of deeds in accordance with his [or her] deeds-if they are good, there will be good recompense, and if evil deeds, there will be an evil recompense. And in this Ayah [i.e. 58:11] is [a mention] of the virtue of knowledge, whose beautification and benefit is that one disciplines [himself or herself] with its etiquettes and act in accordance with what it necessitates. [An Excerpt from ‘Tayseer Al-Kareem Ar-Rahmaan Fee Tafseer Kalaam Al-Mannaan) by Imaam As-Sadi (rahimahullaah). slightly paraphrased]
Imaam Al-Bukhaari [rahimahullaah] said: Chapter: Whoever sat at the farther end of a gathering. And whoever found a place amongst a gathering and took his seat there.”
Narrated Abu Waaqid Al-Laythi [radiyallaahu-anhu]: While Allaah’s Messenger [sallal-laahu-alayhi-wasallam] was sitting in the mosque with some people, three men came. Two of them came in front of Allaah’s Messenger [sallal-laahu-alayhi-wasallam] and the third went away. The two kept on standing before Allaah’s Messenger [sallal-laahu-alayhi-wasallam] for a while and then one of them found a place in the circle and sat there while the other sat behind them [the gathering], and the third went away. When Allaah’s Messenger [sallal-laahu-alayhi-wasallam] finished his gathering, he said, ‘’Shall I tell you about these three persons? One of them betook himself to Allaah, so Allaah took him into His Grace and Mercy and accompanied him, the second felt shy, so Allaah was shy towards him ; while the third turned away, so Allaah turned away from him.” 
Imaam Abdul-Azeez Bin Baaz [rahimahullaah] said: In this [hadeeth] there are beneficial points:
[a] Sometimes he [i.e. the Messenger (sallal-laahu-alayhi-wasallam)] used to have sittings-sometimes in the Masjid and sometimes in the house. [b] It is recommended for the one who enters a masjid whilst there is a gathering that he joins it. [c] In this (hadeeth is evidence about) being eager to benefit (in knowledge); so he enters if he finds a space; but if not he (stays) at the back. [d] In this (hadeeth) there is a warning against turning away from knowledge. 
 Allaah (The Most High) was shy towards him in a way that befits Allaah’s Majesty. Imaam Muhammad ibn Saaleh Al-Uthaymeen (rahimahullaah) said: Allaah’s shyness is not similar to the shyness of the creation. (see Tafseer Soorah Al-Baqarah Ayah 26 by Shaikh Uthaymeen (rahimahullaah)
 [Saheeh al-Bukhaari Vol 1. Hadeeth Number 66]
Al-Hulalul Ibreeziyyah Min At-Ta’liqaat Al-Baaziyyah Alaa Saheeh Al-Bukhaari Vol 1: page 34. Footnote 2