“And those who disbelieve say: Why is not the Quran revealed to him all at once? Thus (it is sent down in parts), that We may strengthen your heart thereby. And We have revealed it to you gradually, in stages.†[25:32].
“And We have revealed it to you gradually, in stages,†means We revealed it slowly and sent it gradually. All of this indicates that Allah was taking care of His Book, the Quran, and His Messenger, Muhammad (peace and blessings of Allah be upon him), as He sent down His Book in accordance with the situations faced by the Messenger and as needed to address unfolding issues. End quote from Tafsir as-S’adi