Well, the Hijri date 15 Rajab 1279 corresponds to the Gregorian date Monday, 5 January 1863. This date lies in the seventh month of the Hijri year 1279 AH, which is Rajab of 1279 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1279/07/15 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 5 January 1863 to its equivalent Arabic date.
The following is the conversion of the Arabic date 15 Rajab 1279 AH to its equivalent Gregorian date.
أُو۟لَٰٓئِكَ ٱلَّذِينَ يَدْعُونَ يَبْتَغُونَ إِلَىٰ رَبِّهِمُ ٱلْوَسِيلَةَ أَيُّهُمْ أَقْرَبُ وَيَرْجُونَ رَحْمَتَهُۥ وَيَخَافُونَ عَذَابَهُۥٓ ۚ إِنَّ عَذَابَ رَبِّكَ كَانَ مَحْذُورًۭا
Those unto whom they cry seek the way of approach to their Lord, which of them shall be the nearest; they hope for His mercy and they fear His doom. Lo! the doom of thy Lord is to be shunned.
Surah Al-Israa(17:57)