Narrated Abu 'Is-haq:

I heard Al-Bara' saying, "The above Verse was revealed regarding us, for the Ansar on returning from Hajj never entered their houses through the proper doors but from behind. One of the Ansar came and entered through the door and he was taunted for it. Therefore, the following was revealed: -- "It is not righteousness That you enter the houses from the back, But the righteous man is He who fears Allah, Obeys His order and keeps away from What He has forbidden So, enter houses through the proper doors." (2.189)

Narrated Al-Bara:

In the Pre-lslamic Period when the people assumed Ihram, they would enter their houses from the back. So Allah revealed:-- "And it is not righteousness that you enter houses from the back, but the righteous man is he who fears Allah, obeys His Orders and keeps away from what He has forbidden. So enter houses through their doors." (2.189)

Bara' reported: When the Ansar performed the Pilgrimage, they did not enter their houses but from behind. A person from the Ansar came and he began to enter from his door but it was said to him (why he was doing something in contravention to the common practice of coming to the houses from behind). Then this verse was revealed." Piety is not that you come to the doors from behind" (ii. 189).