Well, the Hijri date 26 Muharram 1399 corresponds to the Gregorian date Tuesday, 26 December 1978. This date lies in the first month of the Hijri year 1399 AH, which is Muharram of 1399 AH. Both this Hijri and Gregorian date occur on the single day that is Tuesday without any doubt. The Arabic date 1399/01/26 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 26 December 1978 to its equivalent Arabic date.
The following is the conversion of the Arabic date 26 Muharram 1399 AH to its equivalent Gregorian date.
فَقَدْ كَذَّبُوكُم بِمَا تَقُولُونَ فَمَا تَسْتَطِيعُونَ صَرْفًۭا وَلَا نَصْرًۭا ۚ وَمَن يَظْلِم مِّنكُمْ نُذِقْهُ عَذَابًۭا كَبِيرًۭا
Thus they will give you the lie regarding what ye say, then ye can neither avert (the doom) nor obtain help. And whoso among you doeth wrong, We shall make him taste great torment.
Surah Al-Furqaan(25:19)