"In the night in which he was betrayed... ." There are so many options for the lessons on Maunday Thursday. Footwashing, new commandments, and so on. It's all good. It ends though in betrayal.
So much writing on the Lord's Supper makes strong connections between the death of Jesus on Friday and the Supper given to form the community of God's Reign. Other right connections are made to the feast of the Lamb. Some speak strongly of how the taking part in the Supper puts us there with Jesus on Friday or Thursday or with the disciples on the beach or on the road to Emmaus. If it does do that or any of these things, it should note the basic matter: Jesus gives in the midst of betrayal.
So put away the idea of approaching the Supper in purity of thought and heart. Put away some idea of holiness when you administer the sacrament. Gift in the midst of betrayal indicates no one, no community can handle this Supper. Paul was wrong and right: no one can discern the body of Christ.
Tonight, begin the beguine.