Musnad Ahmad Hadith 18332

Abdur Rahman bin Abzi says that a man came to Umar (may Allah be pleased with him) and said, "I am required to perform ghusl but I cannot find water." Umar (may Allah be pleased with him) said, "Do not perform the prayer." Ammar (may Allah be pleased with him) said, "O Commander of the Faithful! Do you not remember that you and I were in an army, and both of us were required to perform ghusl and could not find water? So you did not perform the prayer, while I rolled in the earth and performed the prayer. Then when we came to the service of the Noble Prophet (ﷺ), I mentioned this incident to the Noble Prophet (ﷺ), so the Noble Prophet (ﷺ) said, 'It would have been sufficient for you to do this.' Saying this, the Noble Prophet (ﷺ) struck his hands on the earth, blew on them, and then wiped them over his face and hands." The previous hadith is also narrated through this second chain, ending with Umar's (may Allah be pleased with him) reply, "Why not, we entrust you to whatever you choose."