Even as removing physical leavening is difficult, one metaphorical application of leavening is the lukewarm condition of the Laodicean attitude. Actually, vacuuming our car is a piece of cake when compared to rooting out the leavening of sin in our lives. Brewers and bakers in ancient Egypt learned that the temperature in which yeast propagates the most prolifically is the 68 to 79 degree range, the temperature we call lukewarm. Likewise, sin seems to propagate most favorably when one has a wishy-washy attitude or no zeal. Conversely, when we bake bread at 350 degrees for a certain period of time, the yeast spores die. The two wave loaves described in Leviticus 23:17 had no live yeast spores. Likewise, when we are zealous about our calling, the leavening of sin will become destroyed as well.