Al-Tahāwī said (1): Al-Mughīrah ibn Shu‘bah related that the Messenger of Allah, may Allah bless him and grant him peace, trimmed his moustache over a siwāk (tooth-stick) (2); this does not involve close trimming.
Those who did not favour close trimming cited the two reports from ‘Ā’ishah and Abū Hurayrah traced back to the Prophet: “Ten practices are part of the natural disposition…” (3), which include shortening the moustache. The hadith of Abū Hurayrah (4), recorded by both al-Bukhārī and Muslim (5), states: “Five practices are part of the natural disposition…” and mentions (6) shortening the moustache among them.
Those who favoured close trimming cited the authentic hadiths commanding it, as well as the hadith of Ibn ‘Abbās stating that the Messenger of Allah, may Allah bless him and grant him peace, used to clip his moustache (7).
Al-Tahāwī said: This (8) most likely means close trimming, though it admits both interpretations. Al-‘Alā’ ibn ‘Abd al-Rahmān narrated from his father, from Abū Hurayrah, who attributed it to the Prophet: “Clip the moustaches and let the beards grow” (9). He said: This, too, may mean close trimming. He also related, with his chain of transmission, that Abū Sa‘īd, Abū Usayd, Rāfi‘ ibn Khadīj, Sahl ibn Sa‘d, ‘Abd Allāh ibn ‘Umar, Jābir and Abū Hurayrah used to trim their moustaches closely. Ibrāhīm ibn Muhammad ibn Hātib said: I saw Ibn ‘Umar trim his moustache so closely that it looked as though he were plucking it (10).