"Beasts, birds, reptiles and all kinds of sea-creatures can be, and in fact are, tamed by man, but no one can tame the human tongue. It is an evil always liable to break out, and the poison it spreads is deadly. We use the tongue to bless our Father, God, and we use the same tongue to curse our fellow-men, who are all created in God’s likeness. Blessing and curses come out of the same mouth — surely, my brothers, this is the sort of thing that never ought to happen! Have you ever known a spring to give sweet and bitter water simultaneously? Have you ever seen a fig-tree with a crop of olives, or seen figs growing on a vine? It is just as impossible for a spring to give fresh and salt water at the same time." James 3:7-12
James really gives the best of teaching-metaphors throughout Chapter 3, because they say what they say and yet there's even more behind them...
Think, for a moment, about the nature of a freshwater, sweetwater spring: how would you describe how it "works"? It comes from deep inside the earth; it's cool; it's clean; it's fresh; it brings life and refreshment to them that drink from it. And why can't it bring up bitter water alongside the sweet? Well, because that would mean that the source itself had been tainted; that something was wrong down at its essence; that it no longer is what it was.
And how about the fig tree and the olive tree: what can we learn from looking at their example? Personally, I would say that we see two distinct types of trees, with their own fundamental identities; yet both must source their life from soil, roots, air and water; both will be noted for the quality of their fruit.
So, with both the examples of the waters and the trees, James is not only teaching us about incongruity between fresh- and bitterwater, fig- and olive-trees, he is also pointing our minds and hearts to consider the essence of those things, the inner hidden life from which they spring and grow.
And now listen to James' brother get going on the same tack: “It is impossible for a good tree to produce bad fruit — as impossible as it is for a bad tree to produce good fruit. Do not men know what a tree is by its fruit? You cannot pick figs from briars, or gather a bunch of grapes from a blackberry bush! A good man produces good things from the good stored up in his heart, and a bad man produce evil things from his own stores of evil. For a man’s words will always express what has been treasured in his heart.” (Luke 6:43-45)
Friends, our words are the portal to get a real, true glimpse of what our real, true inner life is like. "For a man’s words will always express what has been treasured in his heart." If our inner life is all caught up in the great adventure of abiding in Jesus by the power of the Holy Spirit, then we'll find our words are becoming His sort of words. It's our relish over the Kingdom of Heaven taking over the landscape of our heart that changes the outflow of our speech: don't forget it!
Truly, gloriously, to Abide in Him alters the very essence of our being!