The Quran frequently refers to issues relating to Truth and lies; distinguishing between them is critical, in many ways the defining point of guidance. In fact, faith itself is predicated on that distinction, the purpose of the Quran and other divine revelations being to guide us to the truth and, as a part of that guidance, to help us recognize and avoid falsehood.
From Al-Nisa’ 4:105:
إِنَّآ أَنزَلْنَآ إِلَيْكَ ٱلْكِتَٰبَ بِٱلْحَقِّ لِتَحْكُمَ بَيْنَ ٱلنَّاسِ بِمَآ أَرَىٰكَ ٱللَّهُ ۚ وَلَا تَكُن لِّلْخَآئِنِينَ خَصِيمًا
We have sent down to you the Book with the Truth that you may judge between the people by that which Allah has shown you, and do not be an advocate for the treacherous.