مسند أحمد

It was narrated from Ibn 'Umar that he said: I saw Sa'd bin Abi Waqqas wiping over his khuffain in Iraq when he did wudoo’ and I objected to that When we met with 'Umar bin al-Khattab, he said to me. Ask your father about what you objected to me doing of wiping over my khuffain, I mentioned that to him and he said: If Sa'd tells you something, do not object to it, for the Messenger of Allah (ﷺ) used to wipe over his khuffain.