This food becomes part of us, and we offer it back to God in lives of loving service. The same thing happens to the air we breathe, the water we drink, the time we spend, the friendships we enjoy. Our task is to take the created world into ourselves and to offer it back to God in lives of loving service to Him and to our neighbors. In the process we sanctify the creation and make it a means of communion with God. Humdrum daily routines, from changing diapers to helping with homework, become transfigured when we realize that they are priestly activities done in love to God through service to people who bear His image.
Ordinary things are indeed holy things.
Driving a school bus, or designing an airplane, or delivering pizzas - every human activity involves doing something with God's created world. When done as service to Him through service to our neighbor, each one can be a priestly offering to Him whose pleasure with our service is life's very highest reward. Nicholas Wolterstorff, in Until Justice and Peace Embrace , suggests that they exist in a rhythmical relationship. The church service is not so different from daily life and work so much in quality as in intensity. On the Lord's day we gather to celebrate what has been happening all week.