Put the gloves on, sparring with my ego
Sparring is a form of practice in fighting sports where one moves in free-form, but not with intent to cause harm (such as by using protective gear). Since he is referring to “gloves”, he is most likely talking about boxing.
Ego serves as a symbol of everything holding him back, personifying his instinct for brash, selfish decisions. Paradoxically, he has to beat himself to become himself; he must conquer his bad habits and ego to be the person he wants to be, but the use of the word sparring (as opposed to punching, say) suggests that this is a prolonged and tumultuous battle.
Macklemore repeatedly references the ego in his other music — he wrote, “Ego want swole until karma catches that up” in “Make The Money”, and dedicated an entire song, “Ego”, to this topic in his 2006 debut album, The Language of My World.
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