Al-Matalib al-'Aliyah 329 — The permissibility of praying in a single

It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "There is no harm for any of you in praying wrapped in his (single) garment (around his whole body), but he should tie it (with a knot) so that it (having to adjust the garment again and again) does not distract him from (the attention and concentration of) his prayer."
Imam Musaddad narrated this hadith in his Musnad. In its chain, the narrator named Abu Harun Umarah bin Juwayn is severely weak and matruk (abandoned) according to the majority of hadith scholars.