In my personal opinion bread represents the body, or the material world. Pretty obvious even today as we are what we eat. However it is significant to Jesus as he taught of the material versus the spiritual worlds, for example:
"Our Father in heaven,
hallowed be your name.
Your kingdom come,
your will be done,
on earth as it is in heaven.
Give us this day our daily bread,
and forgive us our debts,
as we also have forgiven our debtors.
And lead us not into temptation,
but deliver us from evil."
In the Lord's prayer, in my view, earth represents the body and heaven represents our spirit. Both of which actually reside in us (The kingdom of God is inside you - Luke 17:21). So the Lord's prayer is a prayer to wish that the will of the spirit (heaven) comes to reign over the body (earth). The body undergoes lust etc, so if one wishes to overcome lust we must look to the spirit, for example. It can also be taken literally, as can 'bread, water, wine' etc.
Just some ideas, I am not an expert on this.
Thanks, Nicodemus. Your ideas have helped the symbolism from the Christian view make a little better sense to me, although I still wish I had a better understanding of our how the symbolism evolved and if either the Christian sacrament or neopagan ceremony derive from an ancient pagan tradition or if the neopagan ritual is more influenced by Christianity. I suppose I may never know.
I did find a blog that mentioned that Aradia, Gospel of the Witches mentions the cakes and ale ceremony. I looked at Aradia briefly and found this:
"The Conjuration of Meal.
I conjure thee, O Meal!
Who art indeed our body, since without thee
We could not live, thou who (at first as seed)
Before becoming flower went in the earth,
Where all deep secrets hide, and then when ground
Didst dance like, dust in the wind, and yet meanwhile
Didst bear with thee in flitting, secrets strange!"
I know Aradia was influential to Gardner-- however, the authenticity for both Aradia and Gardner's basis for his Wiccan rituals are questioned by historians so I still haven't gotten very far.
I also found a reference in the Encyclopedia of Modern Witchcraft to the cakes and ale ceremony saying it may have been a reference to Jeremiah 44 "in which the Jewish women inform Jeremiah they will go back to offering wine and 'cakes bearing her image' to 'the Queen of Heaven' because in the past when they had followed those practices 'they had plenty of food, and prospered, and saw no evil.'"