We manage to forget even death and then, all of a sudden, in the midst of our "enjoying life" it comes to us: horrible, inescapable, senseless. We may from time to time acknowledge and confess our various "sins," yet we cease to refer our life to that new life which Christ revealed and gave to us. Indeed, we live as if He never came. This is the only real sin, the sin of all sins, the bottomless sadness and tragedy of our nominal Christianity.
If we realize this, then we may understand what Easter is and why it needs and presupposes Lent. For we may then understand that the liturgical traditions of the Church, all its cycles and services, exist, first of all, in order to help us recover the vision and the taste of that new life which we so easily lose and betray, so that we may repent and return to it.
-- Alexander Schmemann, Great Lent: A Journey to Pascha (Crestwood, NY: St. Vladimir's Seminary Press, 2001), pp. 12f.