Well, the Hijri date 15 Rabi Al Awwal 1412 corresponds to the Gregorian date Monday, 23 September 1991. This date lies in the third month of the Hijri year 1412 AH, which is Rabi Al-Awwal of 1412 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1412/03/15 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 23 September 1991 to its equivalent Arabic date.
The following is the conversion of the Arabic date 15 Rabi Al Awwal 1412 AH to its equivalent Gregorian date.
لِيُكَفِّرَ ٱللَّهُ عَنْهُمْ أَسْوَأَ ٱلَّذِى عَمِلُوا۟ وَيَجْزِيَهُمْ أَجْرَهُم بِأَحْسَنِ ٱلَّذِى كَانُوا۟ يَعْمَلُونَ
That Allah will remit from them the worst of what they did, and will pay them for reward the best they used to do.
Surah Az-Zumar(39:35)
Sahih al-Bukhari
Fasting
Chapter: To make up for the missed days of fasting
Narrated `Aisha:
Sometimes I missed some days of Ramadan, but could not fast in lieu of them except in the month of Sha'ban." Said Yahya, a sub-narrator, "She used to be busy serving the Prophet (ﷺ) ."
Sahih al-Bukhari 1950