And no one puts new wine into old wineskins; otherwise the new wine will burst the skins and it will be spilled out, and the skins will be ruined. (Luke 5:37 NASB)
You may not have thought about it yet, but yeast is a living, reproducing microorganism. As such, each type of yeast has it's own genus/species classification with its own specific characteristics. That's important to understand because the yeast we commonly think about is bread yeast, but wine yeast is a completely different organism.
Bread yeast leaves a specific flavor in the dough, works in the top portion of the dough, and is easily killed by the byproducts of its work (the alcohol that is the byproduct of the action of the yeast on the sugar in the dough). Wine yeast, on the other hand, is a hardier organism. Wine yeast does not work only on the top of the juice. The yeast begins its work at the very bottom of the container. Remember that sediment in the must (the skin and pulp)? It settles to the bottom because of its weight. That's exactly where the yeast begins to work, at the deepest point in the vat.
For Christians, the process of transformation can best be accomplished when attention is given early on to all the "root issues" in our lives. Those things that we have hidden away where no one can see but which fuel our responses and actions must be dealt with for us to be free of the past and ready to be transformed. Is there anger, unforgiveness, bitterness, secret sin, or a hurt caused by someone else that has been allowed to fester? It must be addressed.
That's where the yeast work begins. At the bottom of it all. It's the only way for the juice to become wine, and the only way for us to become the transformed and mature person Christ intends.
Pray today that we, and our loved ones for whom we pray, would allow the work of the Holy Spirit to begin at the deepest part of our hearts where our "root issues" are concealed, and that the work would continue until all is healed.