Tafseer Ibn Kathir of AL HAJJ [12]

يَدْعُو مِن دُونِ اللَّهِ مَا لَا يَضُرُّهُ وَمَا لَا يَنفَعُهُ ذَلِكَ هُوَ الضَّلَالُ الْبَعِيدُ

He invokes instead of Allah that which neither harms him nor benefits him. That is what is the extreme error.