Abu Dawud
General Behavior
Book Number: 036 / Hadith Number: 5167
Narated By Abdullah ibn Busr : When the Apostle of Allah (pbuh) came to some people's door, he did not face it squarely, but faced the right or left corner, and said: Peace be upon you! peace be upon you! That was because there were no curtains on the doors of the house at that time.