Well, the Hijri date 21 Dhul Hijjah 1186 corresponds to the Gregorian date Monday, 15 March 1773. This date lies in the twelfth month of the Hijri year 1186 AH, which is Dhu Al-Hijjah of 1186 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1186/12/21 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 15 March 1773 to its equivalent Arabic date.
The following is the conversion of the Arabic date 21 Dhul Hijjah 1186 AH to its equivalent Gregorian date.
وَلَوْ يُؤَاخِذُ ٱللَّهُ ٱلنَّاسَ بِظُلْمِهِم مَّا تَرَكَ عَلَيْهَا مِن دَآبَّةٍۢ وَلَٰكِن يُؤَخِّرُهُمْ إِلَىٰٓ أَجَلٍۢ مُّسَمًّۭى ۖ فَإِذَا جَآءَ أَجَلُهُمْ لَا يَسْتَـْٔخِرُونَ سَاعَةًۭ ۖ وَلَا يَسْتَقْدِمُونَ
If Allah were to take mankind to task for their wrong-doing, he would not leave hereon a living creature, but He reprieveth them to an appointed term, and when their term cometh they cannot put (it) off an hour nor (yet) advance (it).
Surah An-Nahl(16:61)