This Hadith has already been mentioned. See Hadith No. 1274. Different acts have been regarded more meritorious in different Ahadith. For this reason, some scholars have performed the justification that the word mun "whoever" is the keynote in such cases. That is, such and such acts come in the category of eminent acts or they have been mentioned with reference to circumstances and time or place. For instance, at certain times or at certain places or for certain persons, performing Salat in the early prescribed hours is more meritorious, or Hajj through representative or Jihad is more meritorious, etc.
Some scholars are of the opinion that the eminence of different acts has been stressed keeping the person addressed in view.
Linguistically, the word "Hajj" means 'journey to a place one respects'. Technically, it means 'journey to Makkah in order to perform the pilgrimage rites.' The word "Mabrur" is from "Birr" meaning obedience, piety, but it signifies here an act which is done sincerely without committing a sin.