“The Messenger of Allah (ﷺ)
said
to a man: ‘What do you say during your Salat?’ He said: ‘The
Tashah-hud, then I ask Allah for Paradise, and I seek refuge with Him
from Hell, but I do not understand what you and Mu’adh murmur
(during
Salat). He said: ‘Our murmuring revolves around the same
things.’”
Sunan Ibn Majah Book 5, Hadith 108