How shall I render a return to the LORD for all the good He has done for me?

The Eucharist is the New Covenant.

"For I pass on to you what I received from the Lord himself. On the night when he was betrayed, the Lord Jesus took some bread  and gave thanks to God for it. Then he broke it in pieces and said, “This is my body, which is given for you. Do this to remember me.”

In the same way, he took the cup of wine after supper, saying, “This cup is the new covenant between God and his people—an agreement confirmed with my blood. Do this to remember me as often as you drink it.”   (1 Corinthians 11:23-25 NLT)

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