‏النذر : Hadeeth No:4021 Ibn Umar reported that Allaah's Prophet (sallAllaahu alayhi wa sallam) forbade (people) taking vows, and said: It does not (necessarily) bring good (in the form of substantial, and tangible results), but it is the meant whereby something is extracted from the miserly persons....

‏الحج : Hadeeth No:3121 Nafi' reported that 'Abdullah b. Umar (Allaah be pleased with them) used to halt his camel in the stony ground at Dhu'l-Hulaifa, where Allaah's Messenger (sallAllaahu alayhi wa sallam) used to make a halt (and pray)....