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*Originally posted by gupguppy: *
Probably because Hajj had not yet been made obligatory...
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Not a valid point; in that case he (PBUH) should mention 4 pillars, there was no compulsion for him to stick on the digit 5 or 4, if the khums was the 5th pillar before because at that time Hajj was not obligatory then Hajj would be the 6th one.
The importance of Khums remained the same; moreover there was no time period mentioned in hadith however two things show that it is related to some later days. One is age of Ibn Abbas and second is when did people from different tribes started meeting the Holy Prophet.
I have already said that there are many other aAhadith in which different articles and/or acts mentioned and counted with some number count. That number count can be 2, 3, 4, 5, 6, or 7. Even more and on same issue in some other aAadith the count and articles and/or acts are different.