HE said, "...as often as you do THIS..."
the 'this' was the PASSOVER meal.
23For I have received of the Lord that which also I delivered unto you, that the Lord Jesus the same night in which he was betrayed took bread:
24And when he had given thanks, he brake it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me.
25After the same manner also he took the cup, when he had supped, saying, this cup is the new testament in my blood: this do ye, as oft as ye drink it, in remembrance of me.
26For as often as ye eat this bread, and drink this cup, ye do shew the Lord's death till he come.
27Wherefore whosoever shall eat this bread, and drink this cup of the Lord, unworthily, shall be guilty of the body and blood of the Lord.
28But let a man examine himself, and so let him eat of that bread, and drink of that cup.
Once a year.
Chap. IX.The Early, 1st Century Christians did this each Sunday.1. Now as regards the Eucharist (the Thank-offering), give thanks after this manner:
2. First for the cup: "We give thanks to Thee, our Father, for the holy vine of David Thy servant, which thou hast made known to us through Jesus, Thy servant: to Thee be the glory for ever."
3. And for the broken bread: "We give thanks to Thee, our Father, for the life and knowledge which Thou hast made known to us through Jesus, Thy servant: to Thee be the glory for ever.
4. "As this broken bread was scattered upon the mountains and gathered together 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."
5. But let no one eat or drink of your Eucharist, except those baptized into the name of the Lord; for as regards this also the Lord has said: "Give not that which is holy to the dogs."
Chap. X.
1. Now after being filled, give thanks after this manner:
2. "We thank Thee, Holy Father, for Thy Holy Name, which Thou hast caused to dwell (tabernacle) in our hearts, and for the knowledge and faith and immortality which Thou hast made known to us through Jesus Thy Servant, to Thee be the glory for ever.
3. "Thou, O, Almighty Sovereign, didst make all things for Thy Name's sake; Thou gavest food and drink to men for enjoyment that they might give thanks to Thee; but to us Thou didst freely give spiritual food and drink and eternal life through Thy Servant.
4. "Before all things we give thanks to Thee that Thou art mighty; to Thee be the glory for ever.
5. "Remember, O Lord, Thy Church to deliver her from all evil and to perfect her in Thy love; and gather her together from the four winds, sanctified for Thy kingdom which Thou didst prepare for her; for Thine is the power and the glory for ever.
6. "Let grace come, and let this world pass away. Hosanna to the God of David. If any one is holy let him come, if any one is not holy let him repent. Maranatha. Amen."
7. But permit the Prophets to give thanks as much as [in what words] they wish.
....
Chap. XIV.
1. And on the Lord's Day of the Lord come together, and break bread, and give thanks, having before confessed your transgressions, that your sacrifice may be pure.
2. Let no one who has a dispute with his fellow come together with you until they are reconciled, that your sacrifice may not be defiled.
3. For this is that which was spoken by the Lord: "In every place and time offer me a pure sacrifice, for I am a great King, saith the Lord, and my name is wonderful among the Gentiles."