وَلَن تَرۡضَىٰ عَنكَ ٱلۡيَهُودُ وَلَا ٱلنَّصَٰرَىٰ حَتَّىٰ تَتَّبِعَ مِلَّتَهُمۡۗ قُلۡ إِنَّ هُدَى ٱللَّهِ هُوَ ٱلۡهُدَىٰۗ وَلَئِنِ ٱتَّبَعۡتَ أَهۡوَآءَهُم بَعۡدَ ٱلَّذِي جَآءَكَ مِنَ ٱلۡعِلۡمِ مَا لَكَ مِنَ ٱللَّهِ مِن وَلِيّٖ وَلَا نَصِيرٍ
Translation: And never will the Jews or the Christians approve of you until you follow their religion. Say, “Indeed, the guidance of Allah is the [only] guidance.” If you were to follow their desires after what has come to you of knowledge, you would have against Allah no protector or helper.
Al-Baqarah:120
حَدَّثَنَا عُثْمَانُ بْنُ أَبِي شَيْبَةَ، حَدَّثَنَا أَبُو النَّضْرِ، حَدَّثَنَا عَبْدُ الرَّحْمَنِ بْنُ ثَابِتٍ، حَدَّثَنَا حَسَّانُ بْنُ عَطِيَّةَ، عَنْ أَبِي مُنِيبٍ الْجُرَشِيِّ، عَنِ ابْنِ عُمَرَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم
مَنْ تَشَبَّهَ بِقَوْمٍ فَهُوَ مِنْهُمْ ”
Narrated Abdullah ibn Umar:
The Prophet (ﷺ) said: He who copies any people is one of them.
Hasan Sahih (Al-Albani)
Sunan Abi Dawud 4031
In-book: Book 34, Hadith 12
English translation: Book 33, Hadith 4020
Abu Dawood