This is another article in the chapter Probable Enormities from the classical manual on Sharia called Reliance of the Traveller. The articles are posted one by one in the order they are given in the book.
EXCESSIVENESS IN RELIGION
p75.23 Allah Most High says,
“Say: ‘Oh people of the Book, do not be excessive in your religion'” (Koran 4:171).
(Qurtubi:) According to exegetes, this refers to the extremism of the Jews concerning Jesus in accusing Mary of fornication, and the extremism of the Christians in considering him a god. For both excessiveness and remissness are evil, and both may be unbelief (al-Jami’ Ii ahkam at-Qur’an (y1l7), 6.21).
The Prophet (Allah bless him and give him peace) said,
“Beware of going to extremes [in religion], for those before you were only destroyed through excessiveness.”
(Munawi:) Ibn Taymiya says, “His saying ‘Beware of going to extremes in religion’ is a general prohibition applying to all types of extremes, whether in beliefs or works” (Fayd ai-Qadir sharh ai-Jami’ aJ-saghir (y91), 3.126).