What blood ratifies the new covenant?

The blood of Messiah Jesus ratifies this new covenant.

The clearest reference in the Hebrew Scriptures to the New Covenant is in Jeremiah 31:31-34. In this passage there is a contrast between the existing covenant made with the fathers (see Exodus 24:8) and the new covenant that God will make with the house of Israel and Judah in the latter days.

There are four contrasts between the two covenants:

(1) God will write the law in the minds and on the hearts of those in the new covenant

(2) God will be the God of those in the new covenant and they will be His people

(3) the ones in the new covenant will know God, and

(4) God will forgive the iniquities and sins of those in the new covenant.

The main difference is that there will be an internal change and spiritual
metamorphosis of those in the new covenant which will result in a radically different kind of relationship with God.

The context of Jeremiah 31 is God's promise that he will regather Israel in the future and restore her back to her land.

In other passages the New Covenant is called "an everlasting covenant" --
Jer. 32:37-41; 50:5; Isaiah 61:8

It is also called a "covenant of peace" -- Ezekiel 34:25; 37:24-28

In the NT, at Messiah Jesus' last Passover meal he said of the cup of
blessing that this was the blood of the covenant poured out for many (Mark 14:24); the blood of the covenant poured out for many for the forgiveness of sins (Matthew 26:28); the new covenant in my blood (1 Corinthians 11:25); the new covenant in my blood poured out for you (Luke 22:20). What Yeshua (Jesus in Hebrew) was saying is that his death was the means by which the new covenant would come about.

In 2 Corinthians 3:3-18 Paul contrasted the old covenant (identified with
the letter or law) that condemned with the new covenant that brought righteousness (identified with the Spirit). Compare 2 Corinthians 3:3 with Jeremiah 31:33.

The church (all those who have placed their faith in Messiah Jesus) right now benefits from the New Covenant in that all believers enjoy forgiveness of sins and the indwelling of the Holy Spirit (this is the means of the internal spiritual transformation).

The new covenant is also a still future reality and relates to a restored
Israel.

Once the Spirit comes to dwell in the people of Israel in the future, they
will be able to keep the law.

Before Yeshua comes back a 2nd time, Israel will be saved, see Lev. 26:40-42; Deut. 4:29-31; 30:6-8; Isaiah 53:1-9; 59:20-21; Jer. 3:11-18; Ezek. 36:25-27; 37:1-14; Joel 2:28-32; Zech. 12:10-13:2; Matt. 24:30; Rom. 11:26-27; Rev. 1:7. This cleansing is a "prerequisite" for Christ's Second Coming (cf. Matt. 23:37-39).

After Yeshua comes back the 2nd time, he will rule as a king from Israel and she will live in peace in her land. See Deuteronomy. 30:1-10; Isaiah 2:4; 19:23-25; 26:1-4; 32:18; Jeremiah 23:4; 30:10b; Ezekiel 28:26; Amos 9:14-15; Micah 4:4; Zechariah 3:10; 8:4-5; 14:11.

During this time there will be an unparalleled filling of and empowerment by the Holy Spirit on Israel - see Isaiah 32:15; 44:3; Ezekiel 36:24-29; 39:29; Joel 2:28-29.

The New Covenant with Israel will be fulfilled - Jeremiah 31:31-34; 32:35-39; Ezekiel 11:18-20; 16:60-63; 36:25-28; 37:26; Romans 11:26.

There will be a worldwide knowledge of God - Isaiah 2:2-3; 11:9; 54:13;
Jeremiah 31:34; Micah 4:5; Habakkuk 2:14.

The Abrahamic Covenant land-grant boundaries will be established - Genesis 12:7; 13:15, 17; 15:7, 18; 17:8; 24:7; 26:3; 28:13-14; 35:12; 48:4; 50:24; Ezekiel 47:13-48:8, 23-27

And there will be another temple built - Ezekiel 40:5-43:27 (cf. 37:26-28); Zechariah 6:12-15. Gentile nations will assist in this project - Isaiah 60:10-12; Zechariah 6:15; compare Isaiah 66:12.

David Brewer