The Prophet (salla Allahu alaihi wa sallam) said (whih menas), ” Recite surah al Kafirun and then go to sleep after coming to its end, for it is a clearance from shirk.” [Abu Dawud]
Make a habit of reciting this short surah at bed time. Should you die in your sleep, your last words will be a denial of shirk. The reward for reciting this surah is enormous. The reward for its recitation is equivalent to the reward for reciting a quarter of the Quran. [Tirmidhi]
There was a time in Makkah when although a storm of opposition had arisen in the pagan society of Quraish against the message of Islam, yet the leaders of the Kuffar had not lost hope that they could reach some sort of a compromise with Muhammad (sal Allahu alaihi wa sallam). Therefore, they would visit him with different proposals of compromise so that he accept one of them and the dispute between them be brought to an end.
According to Abdullah bin Abbas (radi Allahu anhu), the Quraish proposed to the Prophet (sal Allahu alaihi wa sallam): “We shall give you so much wealth that you will become the richest man of Makkah. We shall give you whichever woman you like in marriage. We are prepared to follow and obey you as our leader, only on the condition that you will not speak ill of our gods. If you do not agree to this, we present another proposal which is to your as well as to our advantage.” This last proposal was that if he (sal Allahu alaihi wa sallam) would worship their gods, Lat and Uzza, for a year, they would worship his God for the same space of time. The Prophet (sal Allahu alaihi wa sallam) replied: “Wait awhile; let me see what my Lord commands in this regard.” Thereupon Surah Kafirun was revealed.
The Quraish had proposed such things to the Prophet (sal Allahu alaihi wa sallam) not once, but at different times and on different occasions; and there was need that they should be given a definite, decisive reply so that their hope of mixing Kufr and Islam on the principle of “give and take” be frustrated for ever.
If this Surah is read with this background in mind, one finds that it was revealed to exonerate the Muslims from the religions of the disbelievers, their rites of worship, their gods, to express total disgust and unconcern with them and to tell them that Islam and Kufr have nothing in common and there is no possibility of their being combined and mixed into one entity.
Although this surah was addressed to the disbelieving Quraish in response to their proposals of compromise, yet it is not confined to them, but having made it a part of the Quran, Allah (subhana wa ta’ala) gave the Muslims the eternal teaching that they should exonerate themselves by word and deed from the creed of Kufr wherever and in whatever form it be, and should declare without any reservation that they cannot make any compromise with the disbelievers in the matter of Islam. That is why this Surah continued to be recited when the people to whom it was addressed as a rejoinder had died and been forgotten