Tafsir of An-Nur 24:28

فٳن لم تجدوا فيها أحدا فﻼإ تدخلوها حتى يوذن لكم

And if you find no one therein, still enter not until permission has been given. This has to do with the way in which one deals with other people's property without their permission. If he wants to, he can give permission, and if he wants to he can refrain from giving permission.

وإن قيل لكم ارجعوا فارجعوا هو أزكى لكم

And if you are asked to go back, go back, for it is purer for you. means, if you are turned away at the door, before or after permission has been given,

فارجعوا هو أزكى لكم

(go back, for it is purer for you), means, going back is purer and better for you.

والله بما تعملون عليم

And Allah is All-Knower of what you do. Qatadah said that one of the emigrants said: "All my life I tried to follow this Ayah, but if I asked for permission to enter upon one of my brothers and he asked me to go back, I could not do so happily, although Allah says,

وإن قيل لكم ارجعوا فارجعوا هو أزكى لكم والله بما تعملون عليم

And if you are asked to go back, go back, for it is purer for you. And Allah is All-Knower of what you do.''

وإن قيل لكم ارجعوا فارجعوا

(And if you are asked to go back, go back....), Sa`id bin Jubayr said, "This means, do not stand at people's doors.''