There is no such thing as a “sin nature.” The Bible never refers to the “sin nature.” It is a myth of modern theology. However, the Bible DOES teach a lot about the “flesh.” This study looks at Ephesians 2:3 to learn what the flesh actually is, and what we are to live in the Spirit rather than in the flesh.

Note that this study is an excerpt from my Gospel Dictionary online course. This course considers 52 key words of the Gospel and thousands of biblical texts. The course contains over 100 hours Bible teaching. You can take the course by joining my online discipleship group.

So let us see what we can learn about the flesh from Ephesians 2:3.

What is the “Flesh” in Ephesians 2:3?

… among whom also we all once conducted ourselves in the lusts of our flesh, fulfilling the desires of the flesh and of the mind, and were by nature children of wrath, just as the others (Ephesians 2:3).

The opening verses of Ephesians 2 contain key ideas for the traditional doctrine of the “sin nature.” It is often taught that these verses clearly describe that the human body is the source of sinful lusts and desires which lead us away from God. It is even sometimes thought that the lusts and desires of the flesh that Paul refers to here are the sexual sins of sensuality that many religious people love to rail against. But several factors reveal what Paul truly has in mind.

First, whatever type of sins Paul has in mind, they do not appear to be of the sensual or sexual variety. When Paul writes that “we all once conducted ourselves” in these behaviors, Paul includes himself as being guilty of these sins. But we know from passages like Philippians 3:3-6, Paul considered himself to be blameless in obedience to the Mosaic Law. He kept the purity laws to such a high degree, he was even able to become a Pharisee. It is unlikely, therefore, that Paul ever committed some of the sexual sins that many read into the text of Ephesians 2:3.

Secondly, and more importantly, the context of Ephesians 2 explains clearly what sort of sins Paul does have in mind. Ephesians 2 follows a “Problem (Ephesians 2:1-3), Solution (Ephesians 2:4-10), Application (Ephesians 2:11-22)” structure.

To properly discover what sort of problem Paul has in mind in Ephesians 2:1-3, we can reverse engineer the chapter and look at the Application section of Ephesians 2:11-22. Nowhere in this section do we read anything about sexual lusts or sensual sins. There is not even a typical “sin list” such as those found elsewhere in Paul’s writings.

Instead, Paul’s primary point of application in Ephesians 2:11-22 is that people who part of God’s family should put aside the various differences and divisions that normally cause strife and separation among us. In Jesus, we should no long allow such separations to exist. Jesus has torn down all dividing walls of hostility, such as those of race, gender, or religion.

Paul’s primary emphasis is on the religious walls of morality that get erected between groups of people. The primary source of enmity between people, says Paul, is found in the laws of commandments and ordinances (Ephesians 2:15). But Jesus exposed the source of this enmity in His own body on the cross, where He put it to death and showed us how we can live together in pace (Ephesians 2:16-18). Now, as a result, we who used to condemn and kill others in the name of God can now love and forgive one another instead (Ephesians 4–5).

So if the application of Paul’s message in Ephesians 2 is that we should no longer kill and condemn others for religious reasons, but should love and live in unity with them instead, this means that the stated problem in Ephesians 2:1-3 must refer to this sinful behavior as well.

And indeed, this is what Paul has in mind.

The “sin” of Ephesians 2:1-3 is not primarily the breaking of the Ten Commandments or living in sensuality. Instead, the sinful behavior of Ephesians 2:1-3 is exactly the sin which Paul himself committed frequently as a zealous, law-abiding, Pharisee. It is the sin of using morality and religion to condemn and kill others in God’s name.

Therefore, when Paul writes about the sins and desires of the flesh, he is referring to the exact thing we have seen elsewhere in this entry about flesh. Paul is thinking about the human mind which sees things only through the physical perspective, and which judges, accuses, and condemns others because they do not follow the same religious laws that we do.

The sin that Paul has in view in Ephesians 2:1-3, and which Jesus revealed to us and delivered us from in Ephesians 2:4-10, is the sin of religious zealots who use their personal obedience to God’s commands as a way to justify hateful and hurtful behavior toward those who do not practice the same levels of obedience.

In such ways, God’s law of love is being used to perpetuate hate. Paul calls his readers to turn away from such fleshly living based on zeal for the law, and follow Jesus into a life of love instead.

Understanding the Gospel requires us to properly understand the key words and terms of the Gospel. Take my course, "The Gospel Dictionary" to learn about the 52 key words of the Gospel, and hundreds of Bible passages that use these words.

This course costs $297, but when you join the Discipleship group, you can to take the entire course for free.

There is no such thing as a “sin nature.” The Bible never refers to the “sin nature.” It is a myth of modern theology. However, the Bible DOES teach a lot about the “flesh.” This study looks at 1 Corinthians 15:35-58 to learn what the flesh actually is, and what we are to live in the Spirit rather than in the flesh.

Note that this study is an excerpt from my Gospel Dictionary online course. This course considers 52 key words of the Gospel and thousands of biblical texts. The course contains over 100 hours Bible teaching. You can take the course by joining my online discipleship group.

So let us see what we can learn about the flesh from 1 Corinthians 15:35-58.

The “Flesh” in 1 Corinthians 15:35-58

All flesh is not the same flesh, but there is one kind of flesh of men, another flesh of animals, another of fish, and another of birds (1 Corinthians 15:39).

Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; nor does corruption inherit incorruption (1 Corinthians 15:50).

One of the first things to note about Paul’s discussion of the bodily resurrection in 1 Corinthians 15 is that he uses the term flesh in reference not only to the human, physical body (sarx and sōma are used interchangeably in 1 Corinthians 15:35-58), but also to the physical body of animals, fish, and birds (1 Corinthians 15:39). If flesh referred to some sort of sinful nature, this text would seem to indicate that animals, fish, and birds also have a sinful nature. Since they do not, it is better to see Paul’s references to flesh as basically synonymous to the physical body made of skin, muscles, and blood.

And yet, as seen in other biblical references, the flesh is more than just the physical body. It also includes the desires and habits of the physical body. This fits perfectly with Paul’s description of the flesh of animals, birds, and fish. Animals are not only different from humans in their physical composition, but also in their fleshly desires, instincts, and habits. This confirms again that flesh is not inherently sinful, but is simply a purely physical, and therefore limited, way of looking at the world and living in it.

God’s Goal for our Flesh

Paul states that our goal, or destiny, is to have our natural bodies become like the spiritual body of Jesus Christ (1 Corinthians 15:42-49). He writes that the natural body comes from dust in the likeness of Adam, but the spiritual body comes from heaven in the likeness of Jesus Christ (1 Corinthians 15:47).

This clearly means that the spiritual body is superior to the natural body. But it does not mean that the natural body is inherently sinful or evil. After all, Jesus had a natural body, and even after His resurrection, His spiritual body was not incorporeal, but was material. He could eat and be touched, but could also pass through walls.

Paul’s point is that the spiritual body of the resurrection is still a physical body, but it will differ in various ways from the natural body we have right now.

Nowhere in this text is a condemnation of the material, fleshly body.

Paul’s only point is that we have one type of body now, and we will have a different type of body in the resurrected stated. It will be more in tune with the things of the Spirit, but it will still be a physical body.

Flesh Cannot Inherit the Kingdom of God?

In regard to life lived according to the flesh, Paul says in 1 Corinthians 15:50 that “flesh and blood cannot inherit the kingdom of heaven.”

It is important to remember first of all that the phrase “inherit the kingdom of heaven” is not equivalent to “going to heaven when we die.” Inheriting the kingdom of heaven is an experience that can be obtained here and now, in this life, before we die. It refers to the practical, day-to-day experience of the rule and reign of God in our lives now.

So when Paul writes about our flesh not being able to experience the rule and reign of God in our lives now, he is pointing out the truth he has written about previously (cf. 1 Corinthians 3:1-4) that life lived according to the flesh is limited in its understanding about how to properly live this life.

Those who live according to the flesh are focused solely on their own physical needs and desires, without any attention given to spiritual truths and godly perspectives. Yes, the fleshly perspective may also include religious zeal for outward obedience to laws and regulations, but such zeal reveals a gaping ignorance of what God really wants from His people.

The spiritual perspective, as seen in Jesus, is one of love, mercy, grace, and forgiveness, and it is this perspective which allows a person to experience the rule and reign of God in their lives now. This perspective will be the only perspective we have in eternity with our glorified spiritual bodies, so as we begin to live in this perspective now, we also begin to gain a preview and foretaste of eternity.

So while the flesh in 1 Corinthians 15 primarily refers to the physical bodies of humans and animals, Paul develops this idea to show that while our resurrected bodies will still be physical, they will also be fully in tune to spiritual realities.

When a person is focused solely on the physical side of life, which includes a zeal for man-made religion, they cannot experience the kingdom of heaven in their life. It is only as we embrace the spiritual principles of love and forgiveness as revealed in Jesus that we will begin to experience all that God wants for us.

Understanding the Gospel requires us to properly understand the key words and terms of the Gospel. Take my course, "The Gospel Dictionary" to learn about the 52 key words of the Gospel, and hundreds of Bible passages that use these words.

This course costs $297, but when you join the Discipleship group, you can to take the entire course for free.