﴿ قُلْ يَٰٓأَهْلَ ٱلْكِتَٰبِ لِمَ تَكْفُرُونَ بِـَٔايَٰتِ ٱللَّهِ وَٱللَّهُ شَهِيدٌ عَلَىٰ مَا تَعْمَلُونَ ﴾

“SAY: "O followers of earlier revelation! Why do you refuse to acknowledge the truth of God's messages, when God is witness to all that you do?"”

(Say: O People of the Scripture! Why disbelieve ye in the revelations of Allah) i.e. in Muhammad and the Qur'an, (when Allah (Himself) is Witness of what ye do) of disbelief, by concealing [the Truth] and engaging in sins?