Just as it was mandatory that the Jews would use AL-Tawrah as 5:47 Tafsir_English translation

﴿وَلۡيَحۡكُمۡ أَهۡلُ ٱلۡإِنجِيلِ بِمَآ أَنزَلَ ٱللَّهُ فِيهِۚ وَمَن لَّمۡ يَحۡكُم بِمَآ أَنزَلَ ٱللَّهُ فَأُوْلَٰٓئِكَ هُمُ ٱلۡفَٰسِقُونَ ﴾
[المَائدة: 47]

Just as it was mandatory that the Jews would use AL-Tawrah as the standard of judgement, so would the Christians; they were commanded to use AL-Injil as the canon law by which to judge matters. He who does not use the standard of judgement as revealed by Allah, shall be wrongful of actions, and such persons are the wicked

ترجمة: وليحكم أهل الإنجيل بما أنـزل الله فيه ومن لم يحكم بما أنـزل, باللغة الإنجليزية تفسير

﴿وليحكم أهل الإنجيل بما أنـزل الله فيه ومن لم يحكم بما أنـزل﴾ [المَائدة: 47]