Musnad Ahmad 2:169

Yahya narrated to us, Humayd narrated to us, from Anas, who said: Umar said: "I agreed with my Lord in three things—or my Lord agreed with me in three things. I said: 'O Messenger of Allah, if only you would take the Station of Ibrahim as a place of prayer?' Then Allah revealed: 'And take the Station of Ibrahim as a place of prayer.' I said: 'O Messenger of Allah, both the righteous and the wicked enter upon you, so if only you would command the Mothers of the Believers to observe the hijab?' Then Allah revealed the verse of the hijab. And it reached me that the Prophet, peace be upon him, had rebuked some of his wives. So I went to the Mothers of the Believers and began to go to them one by one, saying: 'By Allah, either you desist, or Allah will replace His Messenger with wives better than you.' Then I came to one of his wives, and she said: 'O Umar, is there not enough in the Messenger of Allah, peace be upon him, to admonish his wives, that you must be the one to admonish them?' Then Allah revealed: 'It may be that if he divorced you, his Lord would give him in exchange wives better than you.'"