Al Furqan, 32 Ayah
25:32
وَقَالَ ٱلَّذِينَ كَفَرُواْ لَوۡلَا نُزِّلَ عَلَيۡهِ ٱلۡقُرۡءَانُ جُمۡلَةٗ وَٰحِدَةٗۚ كَذَٰلِكَ لِنُثَبِّتَ بِهِۦ فُؤَادَكَۖ وَرَتَّلۡنَٰهُ تَرۡتِيلٗا ٣٢
Wa Qāla Al-Ladhīna Kafarū Lawlā Nuzzila `Alayhi Al-Qur'ānu Jumlatan Wāĥidatan ۚ Kadhālika Linuthabbita Bihi Fu'uādaka ۖ Wa Rattalnāhu Tartīlāan
And those who disbelieve say, "Why was the Qur'an not revealed to him all at once?" Thus [it is] that We may strengthen thereby your heart. And We have spaced it distinctly.