(1) Al-qudhah (with a u-vowel) is the fletching of an arrow. The saying “hadhwa al-qudhah bi-l-qudhah” (“feather to feather”) is a metaphor for close resemblance and unbroken succession, and is cited as a proverb for two things that match exactly without any disparity; see Ibn Manzur, Lisan al-Arab, 4:503, s.v. q-dh-dh. (2) This hadith is among the rigorously authenticated reports that are widely transmitted in the Sahih, Sunan, and Musnad collections. Both al-Bukhari and Muslim record it through multiple chains and with various wordings, yet none of their narrations contains the phrase “hadhwa al-qudhah bi-l-qudhah.” The wording common to both, transmitted from Abu Saʿid al-Khudri, is: “You will surely follow the ways of those before you span by span and cubit by cubit …,” with only minor verbal differences. See: Sahih al-Bukhari, “Book of Holding Fast to the Sunnah,” chapter “The Prophet said: ‘You will surely follow the ways of those before you,’” hadith no. 7320 (Fath al-Bari, 13:300); Sahih Muslim, “Book of Knowledge,” chapter “Imitating the ways of the Jews and Christians,” hadith no. 2669 (4:2054). The wording “hadhwa al-qudhah bi-l-qudhah” is recorded by Ahmad, Musnad, 4:125, and by Ibn al-Athir in Jamiʿ al-usul on the authority of Ruzayn; see Jamiʿ al-usul, 10:34. (3) The noble Companion in question is ʿAbd al-Rahman ibn Sakhr al-Dawsi. He accepted Islam in the seventh year after the Hijrah, remained constantly in the Prophet’s company, and served him, becoming thereby the Companion who transmitted the greatest number of hadith—5,374 in total. One of the Ahl al-Suffah, he once complained to the Messenger of Allah of forgetfulness; the Prophet told him to spread out his cloak, then gathered it up, after which he said, “I never forgot a single hadith thereafter.” ʿUmar later appointed him governor of Bahrain. He returned to settle in Medina, where he died—may Allah be pleased with him—in 59 AH according to the most reliable report. See: Ibn Kathir, al-Bidayah wa-l-nihayah, 8:103–14; Usd al-ghabah, 5:315–16. (4) The word qala (“he said”) is absent from MSS B, C, D and from the printed edition.