Well, the Hijri date 13 Rabi Al Thani 1399 corresponds to the Gregorian date Sunday, 11 March 1979. This date lies in the fourth month of the Hijri year 1399 AH, which is Rabi Al-Thani of 1399 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1399/04/13 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 11 March 1979 to its equivalent Arabic date.
The following is the conversion of the Arabic date 13 Rabi Al Thani 1399 AH to its equivalent Gregorian date.
وَقَالَ فِرْعَوْنُ يَٰهَٰمَٰنُ ٱبْنِ لِى صَرْحًۭا لَّعَلِّىٓ أَبْلُغُ ٱلْأَسْبَٰبَ
And Pharaoh said: O Haman! Build for me a tower that haply I may reach the roads,
Surah Ghafir(40:36)
Sahih al-Bukhari
Oaths and Vows
Chapter: "Allah will not punish you for what is unintentional in your oaths, but He will punish you for your deliberate oaths ..."
Allah's Messenger (ﷺ) also said:
"By Allah, if anyone of you insists on fulfilling an oath by which he may harm his family, he commits a greater sin in Allah's sight than that of dissolving his oath and making expiation for it."
Sahih al-Bukhari 6625