Well, the Hijri date 20 Shawwal 1421 corresponds to the Gregorian date Monday, 15 January 2001. This date lies in the tenth month of the Hijri year 1421 AH, which is Shawwal of 1421 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1421/10/20 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 15 January 2001 to its equivalent Arabic date.
The following is the conversion of the Arabic date 20 Shawwal 1421 AH to its equivalent Gregorian date.
وَإِذْ أَوْحَيْتُ إِلَى ٱلْحَوَارِيِّۦنَ أَنْ ءَامِنُوا۟ بِى وَبِرَسُولِى قَالُوٓا۟ ءَامَنَّا وَٱشْهَدْ بِأَنَّنَا مُسْلِمُونَ
And when I inspired the disciples, (saying): Believe in Me and in My messenger, they said: We believe. Bear witness that we have surrendered (unto Thee) "we are muslims".
Surah Al-Maaida(5:111)
Sahih al-Bukhari
Fasting
Chapter: Ar-Raiyan is for people observing Saum
Narrated Sahl:
The Prophet (ﷺ) said, "There is a gate in Paradise called Ar-Raiyan, and those who observe fasts will enter through it on the Day of Resurrection and none except them will enter through it. It will be said, 'Where are those who used to observe fasts?' They will get up, and none except them will enter through it. After their entry the gate will be closed and nobody will enter through it."
Sahih al-Bukhari 1896