We have revealed the Qur'an in parts that you may recite it to people slowly and with deliberation; and (for that reason) We have revealed it gradually (to suit particular occasions).
و قرآن را به تفاريق نازل كرديم تا تو آن را با تأنى بر مردم بخوانى و نازلش كرديم، نازل‌كردنى به كمال.