Well, the Hijri date 17 Safar 1421 corresponds to the Gregorian date Sunday, 21 May 2000. This date lies in the second month of the Hijri year 1421 AH, which is Safar of 1421 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1421/02/17 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 21 May 2000 to its equivalent Arabic date.
The following is the conversion of the Arabic date 17 Safar 1421 AH to its equivalent Gregorian date.
فَإِذَا هُم بِٱلسَّاهِرَةِ
And lo! they will be awakened.
Surah An-Naazi'aat(79:14)
Sahih al-Bukhari
Witr Prayer
Chapter: What is said regarding the Witr prayer
Narrated Ibn `Abbas:
Once I passed the night in the house of Maimuna (his aunt). I slept across the bed while Allah's Apostle and his wife slept length-wise. The Prophet (ﷺ) slept till midnight or nearly so and woke up rubbing his face and recited ten verses from Surat "Al-`Imran." Allah's Messenger (ﷺ) went towards a leather skin and performed ablution in the most perfect way and then stood for the prayer. I did the same and stood beside him. The Prophet (ﷺ) put his right hand on my head, twisted my ear and then prayed two rak`at five times and then ended his prayer with witr. He laid down till the Mu'adh-dhin came then he stood up and offered two rak`at (Sunnah of Fajr prayer) and then went out and offered the Fajr prayer. (See Hadith 183)
Sahih al-Bukhari 992