When I was in the marines, I became a baker, and later a baking instructor. I liked this for two reasons: first it avoided the militaristic BS that the "grunts" had to endure, and second, bakers had nice little ways of getting even with officers who had to eat the baker's food preparations. I passed on this wisdom to my students when I became an instructor.
Two things about leavening:
1.It will expand within a loaf until it consumes all available fuel
2. Salt acts to retard the growth of leavening
So, as a baker, when I see Jesus telling his followers "ye are the salt of the earth", I see individuals who act to retard the growth of power and general BS.
I find this relationship between leaven and truth to be quite interesting today. For example, in a book by Rudy Rucker called Mind Tools: The Five levels of Mathematical Reality, Rucker explores the relationship between mathematics and truth, and comes to interesting conclusions paralleling the biblical teachings regarding leaven. Here is a statement I found interesting, toward the back of the book:
"Higher properties--such as truth, beauty, or virtue--are prospective. There is no fixed rule or token by which you can recognize the true or the beautiful or the good: these human ideals are not computable. Nor is there any kind of program or attitude that will enable any individual person or school to produce all truth or all beauty or all goodness. Our highest goals are not to be exhausted by the logical working out of any single system."
Let's look at that last statement. It does have a solid connection to the idea of "leavening" in the bible. If any single system continues to grow and grow, and claim to represent truth, whether it is biblical truth, or a god-king who claims his word is truth and cannot be questioned, or any system whatever that seeks to extend itself until it controls all activity, will be false.
We can be certain that such a system will be false. Alonzo Church, who studied Godel's theorem, developed the theorem telling us that no simple yes or no answers can be given for important questions. Godel's theorem tels us that no logical program can hope, even in the limit, to answer all the questions. As Rucker writes:
"After the work of (Alan) Turing, Church, and Godel, the old dream of capturing all truth in a finite logical net can be seen to be thoroughly bankrupt. Turing's analysis of computation suggests that every finitely given logical system(including human beings) is subject to the theorems of Godel and Church. Godel's theorem tells us that no programmatic method can generate all truth; while Church's theorem tells us that we are unable to predict the consequences of the programs that we do devise."
Therefore, if "God" and "truth" are the same, we can be certain that no single religious or logical concept of man can fully represent either one!
No government can represent all truth, and no religion can fully represent God, which strongly suggests that neither church nor state are legitimate authorities over the human mind!
Is that bad? Should we despair because we can never develop such a system? Rucker suggests this to be a reason for joy!
"A world where there is no Godel's theorem would be a world where every property is listable--for any kind of human activity, there would be a programmatic description of how to carry it out[which, after all, is what religions and governments have proposed to do for centuries]. In such a world, it would be possible to learn a hard and fast formula for 'how to be an artist' or 'how to be a scientist'. It would just be a matter of learning the tricks of the trade....Our world is endlessly more complicated than any finite program or any finite set of rules. You're free, and you're really alive, and there's no telling what you'll think of next, nor is there any reason you shouldn't kick over the traces and start a new life at any time".
In history, we see Jesus constantly condemning the "leaven of the Pharisees". And what were the Pharisees doing? Well, constantly condemning and judging those who didn't wash according to tradition, who didn't observe specific rules and formal laws established for standards of "righteousness". In short, they were pretentious.
Not only were they pretentious, but Jesus said they "shut up the kingdom of heaven" and they "take away the key of knowledge" to the people. In short, they taught that it was possible, by observing "programmatic" laws, rules, and rituals, to be "sinless".
In fact, that problem came to a head when Rabbi Hillel, a contemporary of Jesus, stated that, by the process known as his "Seven Laws", it would be possible for humans to establish proper guidelines for obedience to God, that the human mind, in fact, CAN be "subject to God', provided it follows proper procedures and disciplines, or in other words, providing it establishes rote, programmable, finite and rational processes of thought.
Yet that is exactly the process Jesus condemned when he quoted fro Isaiah "In vain do ye worship me, teaching for commandments the doctrines of men". In more modern terms, the Pharisees were creating statutory legislation by which the people could be ruled. It was that very process of statutory legislation that Jesus condemned among the lawyers in Luke 11:52, by saying they "take away the key of knowledge" from the people.
And in fact, that is what Paul directly challenged in Romans 8:7. he told the people that the natural mind, my mind, your mind, is enmity against God and cannot be subject to God. In fact, Paul's statement is mathematically correct! There can be no single system of human thought, in any method of rote or repetition, to represent truth!
That also parallels the statement of Claude Shannon when he developed information theory. The more a message is repeated, the less information it contains. In other words, the more any culture strictly obeys certain rules and rituals because they are convinced those rules and rituals come from some unquestionable source, the less they are able to adapt to change.
That is exactly the same question we face today, in regard to the U.S. Constitution. is it a "living document", or should we follow the "original intent" of the founders?
Believe it or not, when Kurt Godel was studying for citizenship in the U.S., he declared that the laws of the Constitution would lead to dictatorship!
As Godel was preparing fore his citizenship test, a judge mentioned that "wasn't it wonderful that there will be no Hitler in this country?" To which Godel responded that in fact the laws of this country, as written, would very well lead to a dictatorship or tyranny. Fortunately, his friend Einstein, who knew of Godel's misgivings, accompanied Godel to the test, and quickly diverted the conversation away from Godel's findings.
But what led to Godel's conclusions? Palle Yourgrau, in a book titled A World Without Time: The Forgotten Legacy of Godel And Einstein, writes:
"Years later, asked for a legal analogy for his incompleteness theorem, he would comment that a country that depended entirely upon the formal letter of its laws might well find itself defenseless against a crisis that had not, and could not have been foreseen in its legal code. The analogue of his incompleteness theorem, applied to the law, would guarantee that for any legal code, even if intended to be fully explicit and complete, there would always be judgements 'undecided' by the letter of the law".
When you think about it, that is exactly what we are considering regarding Constitutional law today, and was the battle between Jesus and the Pharisees of that time. Can truth be found by any process of finite, programmed, rote law? Jesus and Paul said no, it cannot. The Pharisees said yes, it can. Today, we alternate between "originalism" and "living law". But you will notice that either interpretation, as in the days of the Pharisees, is said to be decided by those who are "experts" in the law.
But there are no such experts, because no single human mind or system can contain all truth!
So again, Jesus and Paul were correct! And from that perspective, so are the atheists today!
There simply exists no "God" that can be contained as a "higher" process of human thought!
There is you, and there is me, and there is our right and obligation to consider others as we consider ourselves.
That, said Jesus, and correctly, is the truthful basis of all law and all commandments.