A new covenant in my blood
The phrase "a new covenant in my blood" is a reference to Jesus' words in Luke 22:20, where he says:
"This cup which is poured out for you is the new covenant in my blood."
In this context, Jesus is speaking to his disciples at the Last Supper, just before he is betrayed and arrested. He is using the cup of wine to symbolize the new covenant that he is about to establish through his sacrifice.
The phrase "new covenant" refers to the idea that Jesus is establishing a new relationship between God and humanity, one that is based on faith and trust in him, rather than on the law and rituals of the Old Testament. The "blood" refers to the sacrifice that Jesus is about to make on the cross, which will be the means by which this new covenant is established.
In other words, Jesus is saying that his blood will be the means by which God's covenant with humanity is renewed and made new. This covenant is not based on human effort or merit, but on the sacrifice of Jesus Christ, who has taken upon himself the sins of humanity and has paid the price for our redemption.
This phrase is also echoed in 1 Corinthians 11:25, where Paul writes:
"This cup is the new covenant in my blood, which is shed for you."
In this passage, Paul is emphasizing the significance of the Lord's Supper, which is a symbol of the new covenant that Jesus has established. He is saying that the bread and wine of the Supper are a reminder of the sacrifice that Jesus made on the cross, and that they are a means by which we can participate in the new covenant that he has established.
Overall, the phrase "a new covenant in my blood" is a powerful expression of the significance of Jesus' sacrifice and the new relationship that he has established between God and humanity.