730. The case of the Holy Supper is similar to that of a treaty, which having been agreed and signed is finally sealed. The Lord Himself teaches us that His blood is a covenant, for He said when He took the cup and gave it:

Drink of it, all of you. This is my blood, the blood of the new testament, Matthew 26:27-28; Mark 14:24; Luke 22:20.

The new testament is the new covenant. This is why the Word written by means of the Prophets before the Lord's coming is called the Old Testament or covenant, and the Word written after His coming by means of the Evangelists and Apostles is called the New Testament or covenant. Blood, and likewise wine in the Holy Supper, means the Divine truth of the Word; see above in 706, 708. The Word too is the actual covenant which the Lord has made with man, and man with the Lord. For the Lord came down as the Word, that is, as Divine truth. It is because this is His blood, that blood in the Israelite church, which represented the Christian church, was called 'the blood of the covenant' (Exodus 24:8; Zechariah 9:11) and the Lord was called 'the Covenant of the people' (Isaiah 42:6; 49:8; Jeremiah 31:31-34; Psalms 111:9).

[2] It is in keeping with the way things are arranged in the world, that there should be a signing as a guarantee, and this follows discussion of the terms. How can anyone have a commission or a will without a signature? How can one have a judgment without a signed decision to make it effective? How can one reach high office in a kingdom without letters patent? How can one get advancement to any office without written confirmation? How can one own a house without a bill of sale or an agreement with the owner? How can one advance towards an end or chase after a goal and so win a prize, unless there is some end or goal where the prize may be won? Or unless the presiding officer has somehow confirmed his offer? These last examples are only added as an illustration to enable even a simpleminded person to grasp that the Holy Supper is a kind of guarantee, seal, token and evidence of commission, to show, even in the sight of angels, that they are sons of God. It is in addition like a key to a home in heaven, where they may reside for ever.