It wasnarrated from Maimunah that when the Prophet (ﷺ) prostrated,hewould hold his forearms away from his sides, such that if a lambwanted to pass under his arms, it would be able to do so. (IT)
English reference (IT): Vol. 1, Book 5, Hadith 880 (IT)
Arabic reference (IT): Book 5, Hadith 929 (IT)