When Sa'd b. Mu'adh suffered affliction on the day of Trench (i.e. the battle of Trench) a man shot an arrow in the vein of his hand. The Messenger of Allah ﷺ pitched a tent for him the mosque so that he might visit him from near.  

لَمَّا أُصِيبَ سَعْدُ بْنُ مُعَاذٍ يَوْمَ الْخَنْدَقِ رَمَاهُ رَجُلٌ فِي الأَكْحَلِ فَضَرَبَ عَلَيْهِ رَسُولُ اللَّهِ ﷺ خَيْمَةً فِي الْمَسْجِدِ فَيَعُودُهُ مِنْ قَرِيبٍ