That Christ should suffer the death of the cross

"THIS kind of death was especially suitable in order to atone for the sin of our first parent, which was the plucking of the apple from the forbidden tree against God's command. And so, to atone for that sin, it was fitting that Christ should suffer by being fastened to a tree, as if restoring what Adam had purloined; according to Psalm 68:5: "Then did I pay that which I took not away." Hence Augustine says in a sermon on the Passion [Cf. Serm. ci De Tempore]: "Adam despised the command, plucking the apple from the tree: but all that Adam lost, Christ found upon the cross." "

~St. Thomas Aquinas: S.T. III, q. 46, art. 4.
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Crucifixion with Mourners and Sts Dominic and Thomas Aquinas (Cell 37),

by Fra Angelico. Fresco, 1441-42; Convento di San Marco, Florence.