Cranach probably drew on input from his lifelong friend Martin Luther when designing these panels, which illustrate the Protestant concept of Law and Gospel.
The left and right "wings" of the paintings illustrate the Protestant concept of Law and Gospel, which emphasizes salvation through the forgiveness of sins in light of the person and work of Jesus Christ.
Now wherever human nature is alone, without the grace of God, the Law cannot be kept, because since Adam's fall in Paradise man is corrupt and has nothing but a wicked desire to sin...
[8] The Prague version unifies the two halves by portraying one man sitting in front of the tree, flanked by a prophet on the left and John the Baptist on the right, both of whom point towards Christ.
While his "baser" lower body points to the "Law" side, his head and torso turn affirmatively toward John and the "Gospel" half.
The painting includes many of the same symbols as the Gotha panel, such as the Brazen Serpent, Moses (at top left), the Fall, and the Crucified and Risen Christ.
[10] For Luther and Cranach, artworks such as Law and Gospel were intended to instill understanding of scripture and Lutheran thought, and the images were deemed acceptable so long as they were subordinate to the written word.
According to Bonnie Noble: Earlier art originated from nonscriptural sources and performed nebulous functions, such as to inspire pious meditations or even private visions.
[11]Thus the didactic format of the painting seeks to define and limit the viewer's response, making it ripe for art-historical criticism less enamored of such moral or instructive values.