Seeking forgiveness by staying silent during the khutbah

He who took a bath and then came for Jumu'a prayer and then prayed what was fixed for him, then kept silence till the Imam finished the sermon, and then prayed along with him, his sins between that time and the next Friday would be forgiven, and even of three days more.  

عَنِ النَّبِيِّ ﷺ قَالَ مَنِ اغْتَسَلَ ثُمَّ أَتَى الْجُمُعَةَ فَصَلَّى مَا قُدِّرَ لَهُ ثُمَّ أَنْصَتَ حَتَّى يَفْرُغَ مِنْ خُطْبَتِهِ ثُمَّ يُصَلِّيَ مَعَهُ غُفِرَ لَهُ مَا بَيْنَهُ وَبَيْنَ الْجُمُعَةِ الأُخْرَى وَفَضْلَ ثَلاَثَةِ أَيَّامٍ  

He who performed ablution well, then came to Friday prayer, listened (to the sermon), kept silence all (his sins) between that time and the next Friday would be forgiven with three days extra, and he who touched pebbles caused an interruption.  

قَالَ رَسُولُ اللَّهِ ﷺ مَنْ تَوَضَّأَ فَأَحْسَنَ الْوُضُوءَ ثُمَّ أَتَى الْجُمُعَةَ فَاسْتَمَعَ وَأَنْصَتَ غُفِرَ لَهُ مَا بَيْنَهُ وَبَيْنَ الْجُمُعَةِ وَزِيَادَةُ ثَلاَثَةِ أَيَّامٍ وَمَنْ مَسَّ الْحَصَى فَقَدْ لَغَا