My LORD’s BibleApostolic Constitutions, Book VII 30
1On the day of the resurrection of the Lord, that is, the Lord's day, assemble yourselves together, without fail, giving thanks to God, and praising Him for those mercies God has bestowed upon you through Christ, and has delivered you from ignorance, error, and bondage, that your sacrifice may be unspotted, and acceptable to God, who has said concerning His universal Church: In every place shall incense and a pure sacrifice be offered unto me; for I am a great King, says the Lord Almighty, and my name is wonderful among the heathen.