Leaven

Leaven is yeast, a substance made of one-celled, microscopic plants which multiply rapidly in the presence of heat and moisture. When yeast reacts with flour it produces a gas (CO2) which causes the dough to rise; when the dough is kneaded, the bubbles of gas are broken down so that the resulting bread is of uniform texture and lightness. Leaven, given time, works through the entire mass of dough so that no part is left untouched. "Leaven leaveneth the whole lump" (I Cor. 5:6). In Scripture,...