Well, the Hijri date 22 Rabi Al Thani 1255 corresponds to the Gregorian date Thursday, 4 July 1839. This date lies in the fourth month of the Hijri year 1255 AH, which is Rabi Al-Thani of 1255 AH. Both this Hijri and Gregorian date occur on the single day that is Thursday without any doubt. The Arabic date 1255/04/22 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 4 July 1839 to its equivalent Arabic date.
The following is the conversion of the Arabic date 22 Rabi Al Thani 1255 AH to its equivalent Gregorian date.
فَإِذَا جَآءَتْهُمُ ٱلْحَسَنَةُ قَالُوا۟ لَنَا هَٰذِهِۦ ۖ وَإِن تُصِبْهُمْ سَيِّئَةٌۭ يَطَّيَّرُوا۟ بِمُوسَىٰ وَمَن مَّعَهُۥٓ ۗ أَلَآ إِنَّمَا طَٰٓئِرُهُمْ عِندَ ٱللَّهِ وَلَٰكِنَّ أَكْثَرَهُمْ لَا يَعْلَمُونَ
But whenever good befell them, they said: This is ours; and whenever evil smote them they ascribed it to the evil auspices of Moses and those with him. Surely their evil auspice was only with Allah. But most of them knew not.
Surah Al-A'raaf(7:131)