Muhammad 47:24. Juz 26, page 509.
أَفَلَا يَتَدَبَّرُونَ ٱلْقُرْءَانَ أَمْ عَلَىٰ قُلُوبٍ أَقْفَالُهَآ٢٤
Will they then not meditate on the Qur'an, or are there locks on the hearts?
Muhammad 47:24, translated by Marmaduke Pickthall