Overall meaning : Allah Almighty says: Say, Muhammad, to my faithful servants to say the gentlest words when speaking to one another, for Satan is ever ready to sow discord and enmity among them. Satan is an outright and sworn enemy to man. Your Lord, mankind, knows who among you is deserving of His mercy and guidance and who is not. If He so wills, He will, by His grace, bestow His mercy on you by showing you the way to it; and if He so wills, He will, in His justice, punish you by not assisting you to tread the way leading to it. Hence, We have not sent you, Muhammad, to keep count of their actions to repay them for them. Your Lord is best aware of all those in the heavens and the earth. We have exalted some prophets above others by such matters as miracles, books and the large number of followers, among other things. To David We gave the Psalms.
The Almighty then enjoins His Prophet to say to the idolaters: Call upon those you claim are gods besides Allah to free you from any harm that afflicts you. They have no power to do so, nor can they transfer it to someone else nor change it in anyway. Allah alone is capable of doing so. Those they claim are gods besides Allah, from among the prophets, the angels and the righteous, themselves strive hard to draw closer to their Lord by hastening to obey Him, hope for His mercy and fear His punishment. The punishment of your Lord is truly something to be feared and avoided. How can the idolaters, then, worship them, this being their case?!