The revelation of the verse of tayammum in one of the expeditions of Year 7 after the Hijrah (7 AH), and from the context of ar-Rahiq al-Makhtum it is understood to be the Expedition of Dhat ar-Riqa'
The verse of tayammum was revealed in this ghazwah in Year 7 after the Hijrah (7 AH). The source material shows that the intended event is the Expedition of Dhat ar-Riqa', one of the expeditions of Year 7 after Khaybar, in which tayammum was legislated.

The verse of tayammum was revealed in this ghazwah in Year 7 after the Hijrah (7 AH). The source material shows that the intended event is the Expedition of Dhat ar-Riqa', one of the expeditions of Year 7 after Khaybar, in which tayammum was legislated.
It represents a legislative aspect of the Sirah that runs alongside military activity, and shows the link between building the state and establishing rulings.
In this ghazwah, the verse of tayammum was revealed.
يَا أَيُّهَا الَّذِينَ آمَنُوا إِذَا قُمْتُمْ إِلَى الصَّلَاةِ فَاغْسِلُوا وُجُوهَكُمْ وَأَيْدِيَكُمْ إِلَى الْمَرَافِقِ وَامْسَحُوا بِرُءُوسِكُمْ وَأَرْجُلَكُمْ إِلَى الْكَعْبَيْنِ ۚ وَإِن كُنتُمْ جُنُبًا فَاطَّهَّرُوا ۚ وَإِن كُنتُم مَّرْضَىٰ أَوْ عَلَىٰ سَفَرٍ أَوْ جَاءَ أَحَدٌ مِّنكُم مِّنَ الْغَائِطِ أَوْ لَامَسْتُمُ النِّسَاءَ فَلَمْ تَجِدُوا مَاءً فَتَيَمَّمُوا صَعِيدًا طَيِّبًا فَامْسَحُوا بِوُجُوهِكُمْ وَأَيْدِيكُم مِّنْهُ ۚ مَا يُرِيدُ اللَّهُ لِيَجْعَلَ عَلَيْكُم مِّنْ حَرَجٍ وَلَٰكِن يُرِيدُ لِيُطَهِّرَكُمْ وَلِيُتِمَّ نِعْمَتَهُ عَلَيْكُمْ لَعَلَّكُمْ تَشْكُرُونَ
During one of the expeditions of Year 7 after the Hijrah (7 AH), the ruling of tayammum was revealed in the Quran, that is, the concession of using clean earth when water is not available or cannot be used. The source material does not mention the reason for revelation here, but links the event to this ghazwah.
This ghazwah came within the military activity after the Treaty of Hudaybiyyah and after Khaybar, and in the context of confronting the movements of some Bedouin tribes in Najd.
The Muslims now had a legal alternative to wudu or ghusl when water was missing or could not be used.
It links one of the ghazwah of the seventh year to the revelation of a Quranic ruling
It shows that revelation met the practical needs of Muslims
It shows the continued management of military affairs by the Prophetic state alongside legislation
It removes hardship from the Muslim community in travel and combat conditions
It teaches ease and compliance with Allah's rulings when one is unable
It lays the foundation for an easy fiqh of purity in the life of the ummah
It combines military movement with building the legislative system
The leader of the ghazwah in which the verse of tayammum was revealed
Those addressed by the ruling of tayammum and the participants in the ghazwah
Revelation comes down to solve real-life acts of worship problems
Relieving hardship from people is among the purposes of the Sharia
Taking into account the community's circumstances in travel and war
The Prophetic state combines security and legislation
Teaching Muslims that worship is never separate from lawful ease
The existence of an organized legal system that takes exceptional cases into account
The Sharia can respond to changing circumstances
The need for eased legal solutions when normal means are not possible
Following legal concessions when their cause is present
The need to explain eased rulings clearly to people
Taking people's circumstances into account in legislation and regulation
To ask about the legal concession when needed and not burden oneself beyond one's ability
The known legal ruling must not be overstepped, and no rulings may be introduced without evidence
The Prophetic context was direct revelation tied to a specific incident, while the modern case is understood from the information and applied with its conditions
If the original legal ruling becomes impossible for a valid excuse, the Muslim moves to the lawful substitute