The Messenger of Allah ﷺ forbade that a man should wrap himself completely in a garment with his hands hidden it, or sit in a single garment with his hands round his knees.
نَهَى رَسُولُ اللَّهِ ﷺ عَنِ الصَّمَّاءِ وَعَنْ الاِحْتِبَاءِ فِي ثَوْبٍ وَاحِدٍ