It is narrated from Sayyiduna Abdullah bin Mas'ud (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Perform Hajj and Umrah one after the other, for they both remove poverty and sins just as the furnace removes the impurities of iron, gold and silver; and the reward of an accepted Hajj is nothing less than Paradise."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 10368