Sunan an-Nasa'i 5479

It was narrated that Mus'ab bin Sa'd and 'Amr bin Maimun Al-Awdi said:"Sa'd used to teach his children these words as a teacher teaches his students, and he would say that the Messenger of Allah [SAW] used to seek refuge (with Allah) with these words at the end of every prayer: 'Allahumma inni a'udhu bika minal-bukhli, wa a'udhu bika mnal-jubni, wa a'udhu bika an uradda ila ardhalil-'umuri, wa a'udhu bika min fitnatid-dunya, wa min 'adhabil-qabr (O Allah, I seek refuge with You from miserliness, and I seek refuge with You from cowardice, and I seek refuge with You from reaching the age of senility, and I seek refuge with You from the trials of this life and the torment of the grave)