Gen 17:10.   This is my covenant, which ye shall keep, between me and you and thy seed after thee; Every man child among you shall be circumcised. Matt 26:27-28.   And he took the cup, and gave thanks, and gave it to them, saying, Drink ye all of it; For this is my blood of the new testament, which is shed for many for the remission of sins. 1 Cor 10:16-18.   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. Behold Israel after the flesh: are not they which eat of the sacrifices partakers of the altar?