Verse 3

ذَٰلِكَ بِأَنَّ ٱلَّذِينَ كَفَرُوا۟ ٱتَّبَعُوا۟ ٱلْبَـٰطِلَ وَأَنَّ ٱلَّذِينَ ءَامَنُوا۟ ٱتَّبَعُوا۟ ٱلْحَقَّ مِن رَّبِّهِمْ كَذَٰلِكَ يَضْرِبُ ٱللَّهُ لِلنَّاسِ أَمْثَـٰلَهُمْ

This is because the unfaithful follow falsehood and the faithful follow the truth from their Lord. God thus cites examples for the people.