It is narrated from Muhammad bin al-Munkadir (may Allah have mercy on him) that Sayyiduna Jabir (may Allah be pleased with him) prayed in a waist-wrapper which he had knotted at the nape of his neck, while his clothes were hanging on the peg. Someone said: "Do you pray in a single garment (even though you have clothes)?" He replied: "Listen! I did this only so that fools like you would see me. Just tell me: in the time of the Messenger of Allah (peace and blessings be upon him), which of us had two garments (because of poverty and hardship)?"
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 3299