Jesus warns us to “Watch out and guard against the leaven of the Pharisees and the leaven of Herod.” In Mark 8:13, Jesus wants us to be wary of all “brands” of leaven, but His. Why? Because the Pharisee’s and Herod’s leaven is all fluff and no "stuff." It looks good and others admire its sheen, but it changes little on the inside. We may look good on the outside, but it doesn’t do what it is supposed to do in the places needed.
It doesn’t cause our hearts to flow with love for others. It doesn’t turn bad habits into needed virtues or give our life that added tang that declares to all “Jesus dwells here. “ No indeed! The Pharisees’ leaven is insipid and bland adding neither freshness nor savour to any and all lives.
The flavour we need to mix into our lives comes only from Jesus, the leaven that increases our desire to aid a neighbour in trouble, and that stirs us to reach out and give food to a hungry brother and sister. And Jesus’ leaven works instantly. It allows our hearts to see plainly the needs of our fellow pilgrims walking with us on our common pilgrimage to the Father.
This leaven unlocks our ears to hear Jesus’ words of hope, promise and mercy coming from the Father. Jesus’ leaven doesn’t want simple obedience to the law, but also an understanding of its beauty. It motivates us to live the law with gratitude to the Father forgiving us so much on a daily basis. This leaven is not magical, but simply mystical giving us a pre-taste of God’s glory and compelling us to share it.
Think about it. If we want to deepen our relationship with Jesus, use only His leaven, because as it rises we become like Him, and better yet act like Him to all around us.