On the day called Sunday all who live in the cities or in the country gather at one place and the memoirs of the apostles or the writings of the prophets are read as long as time permits. When the reader has finished, the one who is presiding instructs us in a brief discourse and exhorts us to imitate these noble things. Then we all stand up together and offer prayers.... When we have finished the prayer, bread is brought forth, and wine and water, and the presiding minister offers up prayers and thanksgiving to the best of his ability, and the people assent, saying the Amen; after this the consecrated elements are distributed and received by each one. Then a deacon brings a portion to those who are absent. Those who prosper, and who so wish, contribute what each thinks fit. What is collected is deposited with the presiding minister who takes care of the orphans and widows, and those who are in need because of sickness or some other reason, and those who are imprisoned, and the strangers and sojourners among us.
From Justin Martyr's First Apology, quoted on pp. 28-29 of Wilken, Robert Louis. The Spirit of Early Christian Thought: Seeking the Face of God. Newhaven: Yale University Press, 2003.
4. Fourth, notice the centrality of the Eucharist (i.e., the Lord's Supper). As in the New Testament (cf. Acts 2:42-47; 1 Cor. 11:17-34), the celebration of the meal Jesus gave us was an absolutely indispensable part of Christian worship - one could say, it was the edible word that stood alongside the audible word, the sermon. For a multitude of historical reasons there isn't time to discuss right now, this practice has often been pushed to the margins in protestant worship especially (despite the insistence of reformers like John Calvin on its centrality to Christian worship). A church that is 'all pulpit and no table' is in a precarious position (as of course is a church that is 'all table and no pulpit'), in danger of forgetting the importance of experiencing and enjoying the life of the kingdom in intimate personal communion with Christ and with his body the church. This need challenges us, beyond the mere question of how often our churches 'do communion,' to ask ourselves whether our churches are places where life is truly being lived 'together' in a meaningful sense.