Well, the Hijri date 16 Rabi Al Thani 1242 corresponds to the Gregorian date Thursday, 16 November 1826. This date lies in the fourth month of the Hijri year 1242 AH, which is Rabi Al-Thani of 1242 AH. Both this Hijri and Gregorian date occur on the single day that is Thursday without any doubt. The Arabic date 1242/04/16 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 16 November 1826 to its equivalent Arabic date.
The following is the conversion of the Arabic date 16 Rabi Al Thani 1242 AH to its equivalent Gregorian date.
وَقَالُوا۟ لَوْ شَآءَ ٱلرَّحْمَٰنُ مَا عَبَدْنَٰهُم ۗ مَّا لَهُم بِذَٰلِكَ مِنْ عِلْمٍ ۖ إِنْ هُمْ إِلَّا يَخْرُصُونَ
And they say: If the Beneficent One had (so) willed, we should not have worshipped them. They have no knowledge whatsoever of that. They do but guess.
Surah Az-Zukhruf(43:20)