the Messenger of Allah (saas) said to a man: "What do you say during your prayer?" He said: "I recite the Tashah-hud then I ask for Allah for Paradise and see refuge with Him from Hell, but by Allah I do not understand your whispering or the whispering of Mu'adh." He said: "It is concerning them (Paradise and Hell) that we are whispering."
قَالَ رَسُولُ اللَّهِ ﷺ لِرَجُلٍ مَا تَقُولُ فِي الصَّلاَةِ قَالَ أَتَشَهَّدُ ثُمَّ أَسْأَلُ اللَّهَ الْجَنَّةَ وَأَعُوذُ بِهِ مِنَ النَّارِ أَمَا وَاللَّهِ مَا أُحْسِنُ دَنْدَنَتَكَ وَلاَ دَنْدَنَةَ مُعَاذٍ قَالَ حَوْلَهُمَا نُدَنْدِنُ