Sayyiduna Abu Hurayrah (may Allah be pleased with him) narrates: The Prophet (peace and blessings be upon him) said: "Help me perform ablution!" I brought him water for ablution. He (peace and blessings be upon him) first cleaned himself after relieving himself (istinja), then put his hand into the soil, wiped it, and then washed it. Then, while performing ablution, he wiped over his leather socks. I said: O Messenger of Allah, will you not wash your feet? He said: When I put them (into the leather socks), they were both pure (that is, I was in a state of ablution).
Imam Ahmad recorded this report; its chain contains a narrator whose name has not been mentioned.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الطهارة / 1346