An-Nur 24:28

فَإِن لَّمْ تَجِدُوا۟ فِيهَآ أَحَدًۭا فَلَا تَدْخُلُوهَا حَتَّىٰ يُؤْذَنَ لَكُمْ ۖ وَإِن قِيلَ لَكُمُ ٱرْجِعُوا۟ فَٱرْجِعُوا۟ ۖ هُوَ أَزْكَىٰ لَكُمْ ۚ وَٱللَّهُ بِمَا تَعْمَلُونَ عَلِيمٌۭ

If ye find no one in the house, enter not until permission is given to you: if ye are asked to go back, go back: that makes for greater purity for yourselves: and Allah knows well all that ye do.