These are the verses of the clear Book. (26:2)

Almuntakhab Fi Tafsir Alquran Alkarim

These are divine verses flowing with the precision and grace symbolic of the Book -the Quran- which is the spirit of truth that guides into all truth

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(26:2) These are the verses of the lucid Book *1

These are the verses of the clear Book. meaning

*1) That is, the verses being presented in this Surah are of that Book, which presents and explains its subject-matter clearly and plainly so that every reader and listener may easily understand what it invites to, what it enjoins and what it forbids, and what it regards as true and what as false. To believe or not to believe is a differen! matter; but no one can have the excuse that he could not understand the teachings of the Book and its injunctions and prohibitions.
"Al-Kitab-ul-Mubin" also has the meaning that the Qur'an is, beyond any doubt, a Divine Book. Its language, its diction and themes, the facts presented by it and the background of its revelations, all testify !o the fact that this is indeed the Book of the Master of all Creation. In this sense, its every sentence is a Sign and a miracle. As such, any person who has common sense has no need of any other Sign than the verses of this Book for believing in the Prophethood of Muhammad (upon whom be Allah's peace and blessings).
This brief introductory sentence, which covers both these meanings, has a close connection with the subject-matter of this Surah. The disbelievers of Makkah demanded a miracle from the Holy Prophet so as to be convinced that the message he gave was really from AIIah. In answer to that, it has been said that if some one really wanted a Sign for believing in the Prophet, he should study the verses of this Book. Then, the disbelievers accused the Holy Prophet of being a sorcerer. This charge has been refuted by saying that the Qur'an has nothing ambiguous or mysterious in it; butit plainly puts forward aII its teachings which cannot be the creation of a poet or a sorcerer's imagination.
 

These are the verses of the clear Book. meaning in Urdu

یہ کتاب مبین کی آیات ہیں