What is the significance of Surah tul Kafiroon?

بِسْمِ اللَّـهِ الرَّحْمَـٰنِ الرَّحِيمِ

 قُلْ يَا أَيُّهَا الْكَافِرُونَ ﴿١﴾ لَا أَعْبُدُ مَا تَعْبُدُونَ ﴿٢﴾ وَلَا أَنتُمْ عَابِدُونَ مَا أَعْبُدُ ﴿٣﴾ وَلَا أَنَا عَابِدٌ مَّا عَبَدتُّمْ ﴿٤﴾ وَلَا أَنتُمْ عَابِدُونَ مَا أَعْبُدُ ﴿٥﴾ لَكُمْ دِينُكُمْ وَلِيَ دِينِ ﴿٦﴾

Summarised from the tafseer of Surah Al Kafiroon by Dr. Farhat Hashmi

The significance of this surah is illuminated by the repeated recitations of this surah by Prophet Muhammad pbuh in his daily salahs. (It is also the surah of tawheed).

Prophet Muhammad pbuh used to recite it in the following rakahs:

1. Every fajr, in the first rakah of the two sunnah of Fajr.
2. At maghrib: first rakah of the two sunnahs after the fard of Maghrib
3. For Witr:  second rakah of witr
4. After Tawaf in the first rakah of the two rakah offered at Muqaam e Ibrahim.
5. At bedtime he would recite it and do Dum (blow on his hands after recitation and pass it over himself) over himself.