Verse 234

وَٱلَّذِينَ يُتَوَفَّوْنَ مِنكُمْ وَيَذَرُونَ أَزْوَٰجًا يَتَرَبَّصْنَ بِأَنفُسِهِنَّ أَرْبَعَةَ أَشْهُرٍ وَعَشْرًا فَإِذَا بَلَغْنَ أَجَلَهُنَّ فَلَا جُنَاحَ عَلَيْكُمْ فِيمَا فَعَلْنَ فِىٓ أَنفُسِهِنَّ بِٱلْمَعْرُوفِ وَٱللَّهُ بِمَا تَعْمَلُونَ خَبِيرٌ

And those who die among you and leave wives behind, the women shall wait an interim of four months and ten days. Then once their interim is over, you commit no error by letting them perform any righteous work on behalf of their souls. And God is All Cognizant of what you do.