Well, the Hijri date 15 Jumada Al Akhira 1400 corresponds to the Gregorian date Wednesday, 30 April 1980. This date lies in the sixth month of the Hijri year 1400 AH, which is Jumada Al-Thani of 1400 AH. Both this Hijri and Gregorian date occur on the single day that is Wednesday without any doubt. The Arabic date 1400/06/15 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 30 April 1980 to its equivalent Arabic date.
The following is the conversion of the Arabic date 15 Jumada Al Akhira 1400 AH to its equivalent Gregorian date.
إِنَّمَا ٱلتَّوْبَةُ عَلَى ٱللَّهِ لِلَّذِينَ يَعْمَلُونَ ٱلسُّوٓءَ بِجَهَٰلَةٍۢ ثُمَّ يَتُوبُونَ مِن قَرِيبٍۢ فَأُو۟لَٰٓئِكَ يَتُوبُ ٱللَّهُ عَلَيْهِمْ ۗ وَكَانَ ٱللَّهُ عَلِيمًا حَكِيمًۭا
Forgiveness is only incumbent on Allah toward those who do evil in ignorance (and) then turn quickly (in repentance) to Allah. These are they toward whom Allah relenteth. Allah is ever Knower, Wise.
Surah An-Nisaa(4:17)