In the Qur'an, 'Ad and Thamud are always mentioned together. Moreover, the verses advise Thamud to take warning from the destruction of 'Ad.
To the Thamud people (We sent) Salih, one of their own brethren: He said: "O my people! worship Allah: ye have no other God but Him" "And remember how He made you inheritors after the 'Ad people and gave you habitations in the land: ye build for yourselves palaces and castles in (open) plains, and carve out homes in the mountains; so bring to remembrance the benefits (ye have received) from Allah, and refrain from evil and mischief on the earth.
From the Sealed Nectar (Raheeq al Makhtoom) by Mubarakpuri:
On their way to Tabuk, the army of Islam (of the Messenger of Allah) passed by Al-Hijr — which was the native land of Thamud who cut out (huge) rocks in the valley; that is "Al-Qura Valley" of today. They watered from its well but later the Messenger of Allâh [pbuh] told them not to drink of that water, nor perform the ablution with it. The dough they made, he asked them to feed their camels with. He forbade them to eat anything whatsoever of it. As an alternative he told them to water from that well which Prophet Salih’s she-camel used to water from.
On the authority of Ibn ‘Umar: "Upon passing by Al-Hijr the Prophet [pbuh] said:
Then he raised his head up and accelerated his strides till he passed the valley out." [Sahih Al-Bukhari 2/637]
"Do not enter the houses of those who erred themselves lest what had happened to them would afflict you, but if you had to do such a thing let it be associated with weeping."
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