The Quran

Preface

يا أَيُّهَا النَّبِيُّ قُل لِأَزواجِكَ وَبَناتِكَ وَنِساءِ المُؤمِنينَ يُدنينَ عَلَيهِنَّ مِن جَلابيبِهِنَّ ۚ ذٰلِكَ أَدنىٰ أَن يُعرَفنَ فَلا يُؤذَينَ ۗ وَكانَ اللَّهُ غَفورًا رَحيمًا

Yusuf Ali

O Prophet! Tell thy wives and daughters, and the believing women,¹ that they should cast their outer garments over² their persons (when abroad): that is most convenient, that they should be known³ (as such) and not molested. And God is Oft-Forgiving,⁴ Most Merciful.

This is for all Muslim women, those of the Prophet’s household, as well as the others. The times were those of insecurity (see next verse) and they were asked to cover themselves with outer garments when walking abroad. It was never contemplated that they should be confined to their houses like prisoners.
Jilbāb, plural Jalābīb: an outer garment: a long gown covering the whole body, or a cloak covering the neck and bosom.
The object was not to restrict the liberty of women, but to protect them from harm and molestation under the conditions then existing in Medīna. In the East and the West a distinctive public dress of some sort or another has always been a badge of honour or distinction, both among men and women. This can be traced back to the earliest civilisations. Assyrian Law in its palmiest days (say, 7th century B.C.), enjoined the veiling of married women and forbade the veiling of slaves and women of ill fame: see Cambridge Ancient History, III, 107.
This rule was not absolute: if for any reason it could not be observed, “God is Oft-Returning, Most Merciful”.