أُو۟لَـٰٓئِكَ ٱلَّذِينَ ءَاتَيْنَـٰهُمُ ٱلْكِتَـٰبَ وَٱلْحُكْمَ وَٱلنُّبُوَّةَ ۚ فَإِن يَكْفُرْ بِهَا هَـٰٓؤُلَآءِ فَقَدْ وَكَّلْنَا بِهَا قَوْمًا لَّيْسُوا۟ بِهَا بِكَـٰفِرِينَ Qur’an Al-An'am (6:89)Olaika allatheena ataynahumu alkitaba waalhukma waalnnubuwwata fain yakfur biha haolai faqad wakkalna biha qawman laysoo biha bikafireena
Lit., "if these deny them" - i.e., the manifestations of God's oneness and of the revelation of His will through the prophets.
i.e., the companions of the Prophet (ﷺ).
Them, i.e., the Book, and authority and Prophethood. They were taken away from the other People of the Book and entrusted to the holy Apostle Muhammad and his People.