31 : 30
ذَٰلِكَ بِأَنَّ ٱللَّهَ هُوَ ٱلۡحَقُّ وَأَنَّ مَا يَدۡعُونَ مِن دُونِهِ ٱلۡبَٰطِلُ وَأَنَّ ٱللَّهَ هُوَ ٱلۡعَلِيُّ ٱلۡكَبِيرُ
That is because Allah is the Truth, and what they supplicate other than Him is false, and it is Allah Who is the Most High, the All-Great.