16-41
And those who migrated in (the cause of) Allah after the injustice that was done to them, We will definitely settle them well in this world and the reward of the hereafter will be greater, if (only) they knew,
The immigrants from Makkah to Madina had patiently suffered the injustices of the polytheists and infidels in Makkah just because they had believed in Allah (SWT) and put their trust in Him. They will therefore be rewarded here as well as in the hereafter.
16-43
And We did not send before you, (messengers) other than men, to whom We had communicated. So ask the people who remember, if you do not know,
Men were sent to mankind as messengers of Allah (SWT) with miracles and Divine books. The Quran has been sent down to make things clear, so that human beings may reflect on its truth and follow it.
16-45
Then, do those who plan evil (things consider themselves) secure that Allah will (not) sink the earth with them, or that the punishment will (not) come to them from directions they do not perceive,
Different ways in which the sinners can be punished are mentioned.
16-48
Or did they not see towards all the things which Allah has created, (how) their shadows return from right and left bowing down to Allah while they are humbly (following His laws)?
Everything in the universe bows down to Allah (SWT) i.e. obey His laws fearing Him.
16-51
And Allah has said, “”Do not take two gods, He is only One God, so fear Me alone.””
Allah (SWT) is the only God, everything in the universe belongs to Him and His laws i.e. Laws of nature prevail, therefore He alone should be feared.
16-53
And whatever (items of) comfort are with you they are from (no one) but Allah. Then when harm afflicts you, to Him (alone) do you cry for help.
All comforts are gifts of Allah (SWT), in adversity people pray to Him but when He removes the adverse conditions some people give the credit to some one else and thus exhibit ingratitude to Him for which they are liable to be punished.
16-56
And they assign a portion from that which We have provided them, to that which they do not (even) know. By Allah, you will definitely be asked about that which you forged.
The polytheists kept aside and presented a part of the wealth which Allah (SWT) had provided them, to false deities (idols), without realizing their worthlessness. They wrongly considered angels as daughters of Allah (SWT) when they themselves regarded daughter very inferior to sons.