Pray that the saints would see that the new covenant promised to Israel in Jeremiah 31:31-34 was absolutely, thoroughly, and completely fulfilled by the Lord Jesus when He established His table and that in instituting the table, He made a covenant with the New Testament believers (Jer. 31:31, 33-34; Matt. 26:26-28; Mark 14:22-25; Luke 22:19-20).
Jer. 31:31, 33-34—Indeed, days are coming, declares Jehovah, when I will make a new covenant with the house of Israel and with the house of Judah…But this is the covenant which I will make with the house of Israel after those days, declares Jehovah: I will put My law in their inward parts and write it upon their hearts; and I will be their God, and they will be My people. And they will no longer teach, each man his neighbor and each man his brother, saying, Know Jehovah; for all of them will know Me, from the little one among them even to the great one among them, declares Jehovah, for I will forgive their iniquity, and their sin I will remember no more.
Matt. 26:26-28—And as they were eating, Jesus took bread and blessed it, and He broke it and gave it to the disciples and said, Take, eat; this is My body. And He took a cup and gave thanks, and He gave it to them, saying, Drink of it, all of you, for this is My blood of the covenant, which is being poured out for many for forgiveness of sins.
Mark 14:22-25—And as they were eating, He took bread and blessed it, and He broke it and gave it to them, and said, Take; this is My body. And He took a cup and gave thanks, and He gave it to them; and they all drank of it. And He said to them, This is My blood of the covenant, which is being poured out for many. Truly I say to you, I shall by no means drink of the product of the vine anymore until that day when I drink it new in the kingdom of God.
Luke 22:19-20—And He took a loaf and gave thanks, and He broke it and gave it to them, saying, This is My body which is being given for you; do this in remembrance of Me. And similarly the cup after they had dined, saying, This cup is the new covenant established in My blood, which is being poured out for you.
For further reading please refer to Life-study of Jeremiah, msg. 39, p. 256 and Life-study of Mark, msg. 43, pp. 375-376.