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.
“The Book” here is the Quran, and the “you” is Prophet Mohammad. This aya clearly states that the Quran was sent down (the literal meaning of the word tanzeel which is often translated as “revealed”) with Truth, which is to be the criterion by which judgment, distinguishing right from wrong, is made. The “treacherous” are those who betray trust; they are in essence liars, betrayers (the literal meaning here) of the Truth, purveyors of falsehood. This is especially critical because the danger of being fooled by lies is always present. The Quran then “grounds” or provides a foundation for the faithful in Truth, from which they can be empowered by that knowledge to make good choices.