15-80
And the inhabitants of Al Hijr (The Rocky Tract) denied the messengers.
Punishment of the people of Saleh (PBH) is mentioned
15-85
And We did not create the skies and the earth and that which is between them both, but in reality. And the hour of doom is certainly coming, so overlook, overlooking in a good manner.
The universe is real and not an illusion, it has been created by Allah (SWT), Who knows everything, to test human beings 11:7
15-87
And We have given you seven of the frequently repeated (verses of Chapter one) and the great Quran.
According to a saying of Prophet Muhammed (PBH) narrated by Abu Hurrairah (R.A) and reported by Bukhari ‘The seven of the frequently repeated’ are the seven verses of the first chapter of the Quran ‘Al Faatiha’.
15-88
Do not strain your eyes (by looking) towards that which We have given for enjoyment to some groups among them, and do not grieve over them and lower your wing to the believers.
Allah (SWT) has given some people things which are items of enjoyment in this world, Prophet Muhammed (PBH) is asked not to look towards these things nor to grieve over their neglecting Islam but to incline and pay his attention to the believers.
15-90
Like that We will send down (the punishment) on the dividers,
These verses may refer to those people who accept part of the Quran which suits them and reject the rest. Some people believe in Allah (SWT) but not in life after death 23:73- 90. Some people do not believe in all messengers 4:150.
15-94
So proclaim that which you are commanded to (proclaim) and turn away from the polytheists.
Prophet Muhammed (PBH) is asked to proclaim Islam openly without bothering about the polytheists because Allah (SWT) is sufficient to help him against them. Then instructions are given to glorify and praise Allah (SWT) bowing down before Him and to serve Him till death.