The necessity of directing worship exclusively to Allah

يَدْعُوا۟ مِن دُونِ ٱللَّهِ مَا لَا يَضُرُّهُۥ وَمَا لَا يَنفَعُهُۥ ۚ ذَٰلِكَ هُوَ ٱلضَّلَـٰلُ ٱلْبَعِيدُ

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