Well, the Hijri date 14 Rabi Al Thani 1277 corresponds to the Gregorian date Monday, 29 October 1860. This date lies in the fourth month of the Hijri year 1277 AH, which is Rabi Al-Thani of 1277 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1277/04/14 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 October 1860 to its equivalent Arabic date.
The following is the conversion of the Arabic date 14 Rabi Al Thani 1277 AH to its equivalent Gregorian date.
۞ قَالَتِ ٱلْأَعْرَابُ ءَامَنَّا ۖ قُل لَّمْ تُؤْمِنُوا۟ وَلَٰكِن قُولُوٓا۟ أَسْلَمْنَا وَلَمَّا يَدْخُلِ ٱلْإِيمَٰنُ فِى قُلُوبِكُمْ ۖ وَإِن تُطِيعُوا۟ ٱللَّهَ وَرَسُولَهُۥ لَا يَلِتْكُم مِّنْ أَعْمَٰلِكُمْ شَيْـًٔا ۚ إِنَّ ٱللَّهَ غَفُورٌۭ رَّحِيمٌ
The wandering Arabs say: We believe. Say (unto them, O Muhammad): Ye believe not, but rather say "We submit," for the faith hath not yet entered into your hearts. Yet, if ye obey Allah and His messenger, He will not withhold from you aught of (the reward of) your deeds. Lo! Allah is Forgiving, Merciful.
Surah Al-Hujuraat(49:14)