"We must never forget that the Church is built around Christ and that, as Sts. Augustine, Thomas Aquinas and Albert the Great have all said, following St. Paul, the Eucharist is the sacrament of the Church's unity, because we all form one single body of which the Lord is the head.
"We must go back again and again to the Last Supper on Holy Thursday, where we were given a pledge of the mystery of our redemption on the cross. The Last Supper is the locus of the nascent Church, the womb containing the Church of every age. In the Eucharist, Christ's sacrifice is constantly renewed, Pentecost is constantly renewed.
. . .
"May all of you become ever more deeply aware of the importance of the Sunday Eucharist," he said, "because Sunday, the first day of the week, is the day when we honor Christ, the day when we receive the strength to live each day the gift of God."
[Pope Benedict XVI, June 22, 2008 - http://www.zenit.org/article-22990?l=english]