Al Baqarah, 120 Ayah
2:120
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 ١٢٠
Wa Lan Tarđá `Anka Al-Yahūdu Wa Lā An-Naşārá Ĥattá Tattabi`a Millatahum ۗ Qul 'Inna Hudá Al-Lahi Huwa Al-Hudá ۗ Wa La'ini Attaba`ta 'Ahwā'ahum Ba`da Al-Ladhī Jā'aka Mina Al-`Ilmi ۙ Mā Laka Mina Al-Lahi Min Wa Līyin Wa Lā Naşīrin
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.