What was the theme representing the interior decorative program of Santa Costanza?

The interior decorative program of Santa Costanza primarily represents themes of resurrection and eternal life, reflecting early Christian beliefs. This is evident in the use of motifs such as grapevines and other agricultural imagery, symbolizing abundance and the promise of salvation. The mosaics and architectural elements emphasize the transition from pagan to Christian symbolism, reinforcing the idea of Christ as the source of life and renewal for the faithful. Overall, the decoration serves to convey theological messages central to early Christianity, particularly the hope of resurrection.