Surah Ali'Imran, Verse 85

وَمَن يَبۡتَغِ غَيۡرَ ٱلۡإِسۡلَٰمِ دِينٗا فَلَن يُقۡبَلَ مِنۡهُ وَهُوَ فِي ٱلۡأٓخِرَةِ مِنَ ٱلۡخَٰسِرِينَ٨٥

waman yabtaghi ghayra l-is'lāmi dīnan falan yuq'bala min'hu wahuwa fī l-ākhirati mina l-khāsirīna

And whoever desires other than Islām as religion - never will it be accepted from him, and he, in the Hereafter, will be among the losers.