Well, the Hijri date 18 Rabi Al Thani 1473 corresponds to the Gregorian date Sunday, 1 January 2051. This date lies in the fourth month of the Hijri year 1473 AH, which is Rabi Al-Thani of 1473 AH. Both this Hijri and Gregorian date occur on the single day that is Sunday without any doubt. The Arabic date 1473/04/18 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 1 January 2051 to its equivalent Arabic date.
The following is the conversion of the Arabic date 18 Rabi Al Thani 1473 AH to its equivalent Gregorian date.
أَمِ ٱتَّخَذُوا۟ مِن دُونِهِۦٓ ءَالِهَةًۭ ۖ قُلْ هَاتُوا۟ بُرْهَٰنَكُمْ ۖ هَٰذَا ذِكْرُ مَن مَّعِىَ وَذِكْرُ مَن قَبْلِى ۗ بَلْ أَكْثَرُهُمْ لَا يَعْلَمُونَ ٱلْحَقَّ ۖ فَهُم مُّعْرِضُونَ
Or have they chosen other gods beside Him? say: Bring your proof (of their godhead). This is the Reminder of those with me and those before me, but most of them know not the Truth and so they are averse.
Surah Al-Anbiyaa(21:24)
Sahih al-Bukhari
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
"Think not that those who rejoice in what they have done (or brought about)..." (V.3:188)
Narrated Alqama bin Waqqas:
Marwan said to his gatekeeper, "Go to Ibn `Abbas, O Rafi`, and say, 'If everybody who rejoices in what he has done, and likes to be praised for what he has not done, will be punished, then all of us will be punished." Ibn `Abbas said, "What connection have you with this case? It was only that the Prophet (ﷺ) called the Jews and asked them about something, and they hid the truth and told him something else, and showed him that they deserved praise for the favor of telling him the answer to his question, and they became happy with what they had concealed. Then Ibn `Abbas recited:-- "(And remember) when Allah took a Covenant from those who were given the Scripture..and those who rejoice in what they have done and love to be praised for what they have not done.' " (3.187-188) Humaid bin `Abdur-Rahman bin `Auf narrated that Marwan had told him (the above narration).
Sahih al-Bukhari 4568