Overall meaning :
Allah Almighty concludes the surah by revealing what He has in store for His believing servants: The All-Compassionate God will bestow His love on those who believe and do righteous deeds, and He will place love and affection in His believing servants’ hearts towards them.
Then, stating the reason for making the Qur’an easy for His Prophet, may Allah bless him and grant him peace, to recite and understand, He says: Indeed, We have made this Qur’an easy in your Arabic tongue, Muhammad, so that you may thereby give those who do what I command and avoid what I forbid the good news that they will enter Paradise in the hereafter and enjoy honour in this world, and to warn the stubborn unbelieving people who seek to confute the truth with false arguments.
The Almighty then concludes by stating His immutable way of dealing with the wrongdoers: We had destroyed many nations before the unbelievers of Quraysh for not believing in Allah and denying His messengers. Do you now perceive a single one of them, or hear even their whisper? By no means. They have all perished, and We will likewise destroy the unbelievers among your people, Muhammad, if they do not seek repentance.