The Prophet ﷺ said, "You will surely follow the ways of those who came before you, hand-span by hand-span and forearm by forearm, until even if they entered a lizard's hole, you would follow them in."We asked, "Messenger of Allah, do you mean the Jews and the Christians?"He replied, "Who else?"
أن النبي ﷺ قال: لتتبعن سنن من قبلكم شبرا بشبر، وذراعا بذراع، حتى لو سلكوا جحر ضب لسلكتموه. قلنا يا رسول الله اليهود والنصاري، قال: فمن؟
Bukhari narrated it in the Book of Holding Fast (7320), and Muslim in the Book of Knowledge (2669), both through Zayd bin Aslam, from Ata bin Yasar, from Abu Saeed Khudri, who related it. The wording given is Bukhari's. Muslim's wording is similar.