The unridden colt symbolizes Jesus' transcendent, non-derivative authority — unlike kings who rode conquered rulers' mounts to claim their power, Jesus' authority is wholly his own.

In the ancient Near East, kings who conquered would ride the previous king's mount or take his concubines as a political claim to power (examples in OT). Jesus riding a colt no one has ridden shows his kingdom is not inherited or derivative — he IS the authority. Parallels Daniel's stone "cut without hands" that destroys worldly kingdoms. Also parallels Jesus being laid in a tomb "in which no one had yet been laid." Winger acknowledges this is somewhat conjectural but finds the symbolism compelling.