From the Didache on the Eucharist
The Didache is one of the earliest known manuscripts of Christianity dating to between 70 and 120 AD. It is more commonly known as the Lord’s Teaching through the Twelve Apostles to the Nations. It is broken into two parts — (1) instruction about the two ways, and (2) a manual of Church order and practice. Here is what it has to say about the early church’s practice in Holy Communion:
Chapter 9. The Eucharist. Now concerning the Eucharist, give thanks this way. First, concerning the cup:
We thank thee, our Father, for the holy vine of David Thy servant, which You madest known to us through Jesus Thy Servant; to Thee be the glory for ever..
And concerning the broken bread:
We thank Thee, our Father, for the life and knowledge which You madest known to us through Jesus Thy Servant; to Thee be the glory for ever. Even as this broken bread was scattered over the hills, and was gathered together and became one, so let Thy Church be gathered together from the ends of the earth into Thy kingdom; for Thine is the glory and the power through Jesus Christ for ever..
But let no one eat or drink of your Eucharist, unless they have been baptized into the name of the Lord; for concerning this also the Lord has said, “Give not that which is holy to the dogs.”
Chapter 10. Prayer after Communion. But after you are filled, give thanks this way:
We thank Thee, holy Father, for Thy holy name which You didst cause to tabernacle in our hearts, and for the knowledge and faith and immortality, which You modest known to us through Jesus Thy Servant; to Thee be the glory for ever. Thou, Master almighty, didst create all things for Thy name’s sake; You gavest food and drink to men for enjoyment, that they might give thanks to Thee; but to us You didst freely give spiritual food and drink and life eternal through Thy Servant. Before all things we thank Thee that You are mighty; to Thee be the glory for ever. Remember, Lord, Thy Church, to deliver it from all evil and to make it perfect in Thy love, and gather it from the four winds, sanctified for Thy kingdom which Thou have prepared for it; for Thine is the power and the glory for ever. Let grace come, and let this world pass away. Hosanna to the God (Son) of David! If any one is holy, let him come; if any one is not so, let him repent. Maranatha. Amen.
But permit the prophets to make Thanksgiving as much as they desire.
Chapter 14. Christian Assembly on the Lord’s Day. But every Lord’s day gather yourselves together, and break bread, and give thanksgiving after having confessed your transgressions, that your sacrifice may be pure. But let no one who is at odds with his fellow come together with you, until they be reconciled, that your sacrifice may not be profaned. For this is that which was spoken by the Lord: “In every place and time offer to me a pure sacrifice; for I am a great King, says the Lord, and my name is wonderful among the nations.”
Read the whole document at earlychristianwritings.com