Matthew 26:28 This is my blood of the covenant, which is poured out for many for the forgiveness of sins.
Not only was Christ reminding the disciples of the blood which was shed for the forgiveness of sins, but He was talking of the blood which was still to be shed – His blood.
Christ was laying down a new promise which he was going to keep – His blood was going to be shed once and for all for all sin and not just for the sin of the people around the table!
Jesus was the ultimate sacrifice who had known no sin and willingly gave Himself to cover all of our sins.