The Messenger of Allah ﷺ said, "Cleansing with stones is done in odd numbers, the stoning at the Jamarat is done in odd numbers, the going between Safa and Marwa is done in odd numbers, and the circumambulation is done in odd numbers. So when one of you cleanses with stones, let him do so in odd numbers."
قال رسول الله ﷺ: الاستجمار تو، ورمي الحمار تو، والسعي بين الصفا والمروة تو، والطواف تو، وإذا استجمر أحدكم فليستجمر بتو.
Muslim narrated it in Hajj (1300), from Salama bin Shabib, who said, Hasan bin Ayan narrated to us, who said, Maqil (that is, Ibn Ubaydullah Jazari) narrated to us, from Abu Zubayr, from Jabir, and he related it.As for his statement "taw," the word taw, with the letter ta pronounced with a short vowel and the waw doubled, means an odd number.As for what is narrated from Saad bin Malik, who said, "We performed tawaf with the Messenger of Allah. Some of us made tawaf seven times, some of us made tawaf eight times, and some of us made tawaf more than that. The Messenger of Allah said, 'There is no harm in that,'" this is daif.Imam Ahmad narrated it (1603), from Surayj bin Numan, who said, Abu Shihab narrated to us, from Hajjaj, from Ibn Abu Najeeh, from Mujahid, from Saad bin Malik, and he related it.Hajjaj here is Ibn Artah, who practiced tadlis and narrated this with an ambiguous form of transmission (an). Also, Mujahid never heard directly from Saad bin Malik, so there is a break in the chain in addition to its weakness.