Sahih Bukhari | Volume 9 | Hadith Number 422

Narrated by Abu Sa'id Al-Khudri
The Prophet said, "You will follow the ways of those nations who were before you, span by span and cubit by cubit (i.e., inch by inch) so much so that even if they entered a hole of a mastigure, you would follow them." We said, "O Allah's Apostle! (Do you mean) the Jews and the Christians?" He said, "Whom else?"