Fadl bin Mubashshir said:
"I saw Jabir bin 'Abdullah performing every prayer with one ablution, and I said: 'What is this?' He said: 'I saw the Messenger of Allah doing this, and I am doing as the Messenger of Allah did.'" (JA)
English reference (JA): Vol. 1, Book 1, Hadith 511 (JA)
Arabic reference (JA): Book 1, Hadith 551 (JA)