Abu Dawud Book 27, Hadith Number 4060.

Chapter : Red color.

Narated By Zaynab : Hurayth ibn al-Abajj as-Sulayhi said: that a woman of Banu Asad: One day I was with Zaynab, the wife of the Apostle of Allah (PBUH), and we were dyeing her clothes with red ochre. In the meantime the Apostle of Allah (PBUH) peeped us. When he saw the red ochre, he returned. When Zaynab saw this, she realised that the Apostle of Allah (PBUH) disapproved of what she had done. She then took and washed her clothes and concealed all redness. The Apostle of Allah (PBUH) then returned and peeped, and when he did not see anything, he entered.