Ka'b b. 'Ujra reported Allaah's Messenger (sallAllaahu alayhi wa sallam) as saying: There are certain ejaculations, the repeaters of which or the performers of which after every prescribed prayer will never be caused disappointment:" Glory be to Allaah" thirty-three times." Praise be to Allaah" thirty-three times, and" Allaah is most Great" thirty-four times.