Luke 22:20 = late interpolation (words taken from 1 Corinthians 11:25)

In Luke’s gospel, Jesus’ death is not a sacrifice for sins whereas other gospels stress that his sacrifice of flesh and shedding of blood brought salvation.

We might think otherwise due to Luke 22:20: “This cup is the new covenant in my blood which is shed for you.”

But this was added by later scribes. The line is not in the earliest copies of Luke’s gospel.

If Luke did not write the line, where did the words come from? Not from the imagination of any scribe but from Paul’s first letter to the Corinthians.

Here is 1 Corinthians 11:25: “...after supper he took the cup, saying, ‘This cup is the new covenant in my blood; do this, whenever
you drink it, in remembrance of me.’”

What is stated here is a simplified summary of what I found in books by Bart Ehrman, who summarizes positions held by various Biblical scholars.