Sufficiency of Allah's knowledge

لَّـٰكِنِ ٱللَّهُ يَشْهَدُ بِمَآ أَنزَلَ إِلَيْكَ ۖ أَنزَلَهُۥ بِعِلْمِهِۦ ۖ وَٱلْمَلَـٰٓئِكَةُ يَشْهَدُونَ ۚ وَكَفَىٰ بِٱللَّهِ شَهِيدًا

But Allāh bears witness to that which He has revealed to you. He has sent it down with His knowledge, and the angels bear witness [as well]. And sufficient is Allāh as Witness.