At the Last Supper, Jesus said:
"This cup is the New Covenant in my blood, which is shed for you." Luke 22:20
This is the only time Jesus explicitly mentions the New Covenant. He does not explain it, because His disciples already knew what God had declared centuries earlier.
This New Covenant was declared by the Lord over 600 years before Christ, when the Word of the Lord spoke through the prophet Jeremiah:
"The days are coming, deczzlares the Lord, when I will make a New Covenant... It will not be like the Covenant I made with their ancestors. I will forgive their iniquity, and I will remember their sin no more.
The New Covenant fulfills the previous covenants, this is why Jesus said:
"Do not think that I have come to abolish the Law or the Prophets;
I have not come to abolish them but to fulfill them." Matthew 5:17What is this New Covenant?
God made several covenants in Scripture-binding promises that established His relationship with humanity: the covenant with Noah, the covenant with Abraham, the covenant given through Moses, the covenant with David. The New Covenant is the foundation of Christianity, declared more than six hundred years before Christ, when the Word of the Lord spoke through the prophets.God's New Covenant forgave our sins and, most importantly, the Word of the Lord through Ezekiel declared His will for the New Covenant:
"I will give you a new heart...and I will put My Spirit within you." Ezekiel 36:27