We should be reluctant to criticize because many symbols are referred to in the bible. It is ourselves the student who should understand and not condemn that which is not understood. Explore and investigate the parables of Jesus, which were used to both conceal and dramatize doctrines. Knowledge is light, if given to much to soon we are blinded. Beginning with a soft glow and increasing it can become a revealer of things hidden in darkness.
Symbolism helps each student add to that light which they now contain.
In Fact Conceal Doctrine. The eyes of some were blinded on purpose because some were troublemakers. We would not understand all doctrine if it was dumped on us, we would be blinded. First the milk then the meat. Understand the basic symbols then start learning the more advanced doctrine.