Former Archbishop of Canterbury and Anglican theologian Rowan Williams:
The Eucharist reminds us of the need for honest repentance – of the need to confront our capacity to betray and forget the gift we have been given. And that is why the Eucharist is not, in Christian practice, a reward for good behavior; it is the food we need to prevent ourselves from starving as a result of our own self-enclosure and self-absorption, our pride and our forgetfulness.
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We take Holy Communion not because we are doing well, but because we are doing badly. Not because we have arrived, but because we are traveling. Not because we are right, but because we are confused and wrong. Not because we are divine, but because we are human. Not because we are full, but because we are hungry.
And so that element of self-awareness and repentance is completely bound up with the nature of what we are doing in the Holy Eucharist: the celebration and the sorrow, the Easter and the cross are always there together. And we come together as Christians, we come not to celebrate ourselves and how well we are doing, but to celebrate the eternal Gift that is always there, and to give the thanks that are drawn out of us by that Gift.
– Being Christian: Baptism, Bible, Eucharist, Prayer