Sahih al-Bukhari 345

Bishr ibn Khalid narrated to us: Muhammad—Ghundar—narrated to us, from Shu‘bah, from Sulayman, from Abu Wa’il, who said: Abu Musa said to Abd Allah ibn Mas‘ud, ‘If someone cannot find water, he does not pray.’ Abd Allah replied, ‘If I were to grant people a concession in this, then whenever one of them felt cold, he would do the same’—meaning perform tayammum and pray. I said, ‘Then what about Ammar’s statement to Umar?’ He said, ‘I did not see Umar satisfied with Ammar’s statement.’