Well, the Hijri date 18 Dhul Qidah 1378 corresponds to the Gregorian date Monday, 25 May 1959. This date lies in the eleventh month of the Hijri year 1378 AH, which is Dhu Al-Qidah of 1378 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1378/11/18 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 25 May 1959 to its equivalent Arabic date.
The following is the conversion of the Arabic date 18 Dhul Qidah 1378 AH to its equivalent Gregorian date.
۞ وَلَقَدْ ءَاتَيْنَآ إِبْرَٰهِيمَ رُشْدَهُۥ مِن قَبْلُ وَكُنَّا بِهِۦ عَٰلِمِينَ
And We verily gave Abraham of old his proper course, and We were Aware of him,
Surah Al-Anbiyaa(21:51)