Bringing up David in a discussion of Christian worship is about as lame as it can get. The Ark of the Covenant is now in Heaven, there is no Temple in Jerusalem, and those who worship truly must worship in Spirit and in truth. The Lord's Supper is where Christians worship and commune with God and Christ. For the early Christians, this was a weekly "Remembrance Feast".
The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ? For we being many are one bread, and one body: for we are all partakers of that one bread...Ye cannot drink the cup of the Lord, and the cup of devils: ye cannot be partakers of the Lord's table, and of the table of devils. (1 Cor 10:16,17,21)
The Roman Catholic Mass is a PERVERSION of the Lord's Supper, and for that reason alone the RCC should be shunned.