Leaven comes up a lot in the Bible. We first see it in the story of the exodus when God tells Israel not to put leaven in their bread the night before He delivers them from the captivity in Egypt (Ex 12). God further explains to Moses that the people of Israel are to celebrate this incredible moment of deliverance by cleaning all the leaven from their homes (Ex 12:14–15).
Jesus too talks about leaven in the New Testament. Jesus says in Mark 8:15, “Watch out. Beware of the yeast of the Pharisees and the yeast of Herod.”
What is this all about?
Almost always in the Bible yeast, or leaven, is symbolic of sin. The point of comparison between them is that a little bit goes a long way. It only takes a pinch of yeast to make an entire loaf of bread rise. Sin is the same way. It only takes a pinch of sin to take people and the world to ruin. Sin, like yeast, is not static, it’s organic. It constantly spreads like a powerful disease.
This is why it is essential that Israel gets rid of all the yeast in their homes when celebrating their salvation. It is an object lesson that teaches God’s people that they have to be diligent and militant when it comes to dealing with sin. John Owen once said, “Be killing sin, or sin will be killing you.”
This is also why what seems to be a little bit of sin in the Garden of Eden is able to disrupt God’s creation project. God’s mission to fill the creation with his glory via humanity is disrupted in Genesis 3 when Adam and Eve rebel against him. In Genesis 3, the self-giving became self-consumed. The caring and wise became the tyrannical and foolish (Rom 1:20–23). In Genesis 3, the reign of life was exchanged for the reign of death (Rom 5:12). In sum, humanity’s rebellion thwarts God’s mission to fill the creation with his glory via humanity.
Being displaced from God’s presence wreaks havoc on human nature. Sin isn’t just about failing to conform to the will of God, it’s a matter of nature. It’s not just about what we do, but who we are. Spending too much time in darkness alters the fabric of human existence. Wayne Grudem writes,
Sin disrupts everything. We don’t live the lives we were originally designed to live, and we don’t live in the world we were originally designed to live in. Sin mars the image of God in us; we no longer reflect the perfection God created us to reflect. Because of sin, things simply aren’t the way they were originally meant to be. The story of the human race, as presented in the Bible, is the story of God fixing broken people living in a broken world. It is the story of God’s victory over the many results of sin in the world.
Sin is a disease that alters our genetic make-up. It creates an unwavering proclivity to self-centeredness. It gets us stuck into the pattern of thinking that we are at the center of all that is and matters. Martin Luther aptly described the sinful nature of humanity as people being “bent inward on themselves.”
This is the opposite of who God is. The Trinity is self-giving. Each Person of the Trinity freely gives themselves away. They live for the other. They live to serve the other. They live for the life and joy of the other. Jesus’s death on the cross is the best image of what this sort of living looks like. In Philippians 2:3–5 Paul urges the Christians at Philippians to imitate Jesus. Paul says,
Do nothing from selfish ambition or conceit, but in humility regard others as better than yourselves. Let each of you look not to your own interests, but to the interests of others. Let the same mind be in you that was in Christ Jesus…
This is the opposite of the sin nature. It’s unnatural for humans.
We will see later on that the sin nature is precisely why God’s Law written on tables of stone simply doesn’t solve the sin problem. This is why we need another Pentecost. Giving the Law on tables of stone cannot circumcise the heart. It’s not only what we do, think, and feel that is offensive to God, but who we are. We need a transformation of our very nature. This is what the Holy Spirit’s ministry is all about.
Thankfully, God doesn’t give up on his creation project. He will rescue it by forming and filling yet again. Just like he did in the creation account of Genesis 1, God will make a new tabernacle and a new Adam so as to reestablish His righteous reign over the creation with his regenerated image-bearers.
The Rescue Plan: Election, Covenant, Atonement, and the Temple
One of the most compelling things about the story of God’s creation-rescue plan is that He chooses to accomplish it through people. God chooses to save the world through Abraham’s family (Gen 12, 15, and 17). God chose Abraham and his family to be the new humanity—His new image-bearers. This is what makes Abraham’s family the chosen (or “elect”) people of God—that God chose through them to rescue the world. Through Abraham’s family, God’s special presence and glory will return once again to the creation in a way that is visible to all. Through the line of Abraham, God will undo what Adam did.
God’s promise to Abraham to fulfill His rescue plan through his family comes to a climax in the book of Exodus. It’s an incredible story. God first delivers Israel from slavery in Egypt, then he leads them out of Egypt by way of the Red Sea. After the miraculous Red Sea crossing, God takes them to Mount Sinai to make a covenant with them. The covenant makes their relationship legal, just like a wedding, or an adoption. If God and Israel were going to belong to one another, then they needed to establish the terms for the relationship. This is a lot like the Garden of Eden all over again.
In this covenant, both parties—God and Israel—agree to uphold their respective requirements of the contract. These requirements are known as the covenant stipulations. God promises to give Israel the Promised Land, protect Israel, provide for them abundant living, and to live in their midst. In return, Israel promises to obey the Ten Commandments—or the “Law” (i.e., God’s instructions on how to carry out daily and ceremonial life). To seal the covenant, Moses performs a ceremony in which he sacrifices oxen and dashes the blood of the oxen first on the altar of God, and then on Israel (Ex. 24). The sign of blood means that the consequence of violating the covenant is death.
The importance of the giving of the Law at Sinai cannot be overstated. It is arguably the single most important event in the Old Testament. Its importance is underlined through God’s command for Israel to celebrate this event annually in a pilgrimage festival (Ex 23:16; 34:22; Nu 28:26; Dt 16:9). That festival is Pentecost. Pentecost commemorates God giving the Israelites the covenant at Sinai.
But why are Pentecost and the giving of the Law at Sinai so important? It’s important because the Law is the means through which God’s mission to fill the earth with his glory is restored. The Law is the way in which Genesis 3 would be undone. The Law was intended to be the instrument through which God’s creation reboot project would be activated in ancient Israel. The Law would make Israel look like Adam was supposed to look from the very beginning. It was supposed to restore the image of God in humanity. It was intended to get God’s mission back on track. When Genesis 3 happened, humanity lost its capacity to reflect God—to testify to the goodness of the Creator. This is corrected by the Law. In the Law, the reign of corruption and selfishness in humanity is intended to be corrected. Said another way, the Law was the means for Israel to be the walking, breathing witness to God’s self-giving, just, loving, and holy nature once again. The Law sets out the code for human behavior as God intended it. If they left behind the ways of Adam and lived according to God’s Law, then his glory could fill the creation. As the commands of God encoded in the Law are ultimately a picture of who God is and a promise of what people can become, then the Law must be missional.
We will see later that understanding this missional purpose of the Law is key to understanding the role and function of the Holy Spirit in the New Testament. It is no coincidence that God poured out the Holy Spirit on the same day that commemorated when he gave Israel the Law at Sinai. That day is Pentecost. In particular, we will see that the Holy Spirit and the Law have the same purpose: to bring the glory of God to the ends of the earth through the testimony of the human heart that is shaped in his likeness. More on this later.
(Editor's Note: This article was first posted HERE on Dr. Ayars website).