Overall meaning :
This surah begins with some of the ‘disconnected letters’, which have already been discussed at the beginning of Surat Al-Baqarah. The Almighty then says: These great verses are the verses of the Qur’an, a book whose truth is very clear and which makes the truth abundantly manifest. It is guidance and good news for the believers, those who duly perform the prescribed prayers with all their pillars, conditions and the manner they ought to be performed, pay the prescribed zakat to those eligible for it and firmly believe in the life to come and in the divine judgement and recompense on Judgement Day.
Regarding those who do not believe in the life to come, We have made their evil deeds look good and seem fair to them, as punishment for their unbelief and for their preferring blindness over guidance, and so they wander about blindly and are never guided to the truth. These will receive the severest punishment and will be the greatest losers in the hereafter they will be the losers for taking error and misguidance in exchange for guidance.
Surely you, Muhammad, are receiving this Qur’an and are being taught it by Gabriel (Jibreel), who has been sent to you by the All-Wise, who puts things in their proper places; the All-Knowing, who knows the apparent and hidden aspects of all things.