One of the traditional hallmarks of Lent is self-denial. In a hymn we sang yesterday, we tell the Lord we intend to "die to self and only live by your most holy Word." As familiar as this sounds to a lifelong Catholic, it turned out to be an unsettling concept to someone not brought up in our Catholic spiritual environment. I overheard a snippet of conversation in which someone was asking what that terrible expression ("die to self") meant. When it was rephrased as "die to selfishness," that seemed to work.
Self-denial is the opposite of self-indulgence or self-satisfaction: a life built on these is a pretty ugly sight. In today's Gospel, Jesus tells us pretty forthrightly: "If anyone wishes to come after me, he must deny himself....losing his life for my sake." Only Jesus makes full sense of this. Self-denial without the "follow me" is just stoicism.