Well, the Hijri date 28 Shaban 1399 corresponds to the Gregorian date Sunday, 22 July 1979. This date lies in the eighth month of the Hijri year 1399 AH, which is Shaban of 1399 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1399/08/28 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 22 July 1979 to its equivalent Arabic date.
The following is the conversion of the Arabic date 28 Shaban 1399 AH to its equivalent Gregorian date.
وَإِذَا جَآءَتْهُمْ ءَايَةٌۭ قَالُوا۟ لَن نُّؤْمِنَ حَتَّىٰ نُؤْتَىٰ مِثْلَ مَآ أُوتِىَ رُسُلُ ٱللَّهِ ۘ ٱللَّهُ أَعْلَمُ حَيْثُ يَجْعَلُ رِسَالَتَهُۥ ۗ سَيُصِيبُ ٱلَّذِينَ أَجْرَمُوا۟ صَغَارٌ عِندَ ٱللَّهِ وَعَذَابٌۭ شَدِيدٌۢ بِمَا كَانُوا۟ يَمْكُرُونَ
And when a token cometh unto them, they say: We will not believe till we are given that which Allah's messengers are given. Allah knoweth best with whom to place His message. Humiliation from Allah and heavy punishment will smite the guilty for their scheming.
Surah Al-An'aam(6:124)