It is narrated from Hazrat Abu Dharr (may Allah be pleased with him) that once he became obliged to perform ghusl. In that state, he came to the Prophet Muhammad (peace and blessings be upon him). The Prophet (peace and blessings be upon him) had water brought for him. He performed ghusl behind a curtain. Then the Prophet (peace and blessings be upon him) said to him: Pure earth is a means of ablution for a Muslim, even if he does not find water for ten years. When water is found, he should pour it over his body, for that is better for him.