Well, the Hijri date 13 Rabi Al Thani 1431 corresponds to the Gregorian date Monday, 29 March 2010. This date lies in the fourth month of the Hijri year 1431 AH, which is Rabi Al-Thani of 1431 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1431/04/13 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 29 March 2010 to its equivalent Arabic date.
The following is the conversion of the Arabic date 13 Rabi Al Thani 1431 AH to its equivalent Gregorian date.
حَتَّىٰٓ إِذَا جَآءُو قَالَ أَكَذَّبْتُم بِـَٔايَٰتِى وَلَمْ تُحِيطُوا۟ بِهَا عِلْمًا أَمَّاذَا كُنتُمْ تَعْمَلُونَ
Till, when they come (before their Lord), He will say: Did ye deny My revelations when ye could not compass them in knowledge, or what was it that ye did?
Surah An-Naml(27:84)
Sahih al-Bukhari
Fasting
Chapter: To hasten the Iftar
Narrated Ibn Abi `Aufa:
I was with the Prophet (ﷺ) on a journey, and he observed the fast till evening. The Prophet (ﷺ) said to a man, "Get down and mix Sawiq with water for me." He replied, "Will you wait till it is evening?" The Prophet said, "Get down and mix Sawiq with water for me; when you see night falling from this side, the fasting person should break his fast."
Sahih al-Bukhari 1958