We are delighted to hear that the New International Version of the Bible has made a key change in its 2011 update which has recently been released (in electronic form only at this point). The Greek word sarx is now rendered "flesh" rather than "sinful nature".
Why does this matter? Here is what we say in Session 5 of the Freedom In Christ Discipleship Course:
“Flesh” is an unfamiliar word to the modern ear in this context, but it’s exactly what the original Bible text says. The Greek word used in the New Testament (‘sarx’) was the word used to describe, for example, meat you would buy from a butcher or the flesh on your leg.
Many modern Bible translations do not translate the word “flesh” literally but interpret it and use a phrase such as “sinful nature” or “old nature” (though you will normally find a footnote explaining what they have done). That is understandable. Using a direct translation without explanation would not make a great deal of sense to modern readers. However, using the term “nature” can be unhelpful because, as we have seen, Christians definitely do not any longer have a sinful nature but share God’s nature. Deep down inside at the most fundamental level of our nature and identity we are now holy and righteous.
The translators’ notes to the NIV update say this:
Most occurrences of “sinful nature” have become “flesh.” Especially in Paul, sarx can mean either part or all of the human body or the human being under the power of sin. In an effort to capture this latter sense of the word, the original NIV often rendered sarx as “sinful nature.” But this expression can mislead readers into thinking the human person is made up of various compartments, one of which is sarx, whereas the biblical writers’ point is that humans can choose to yield themselves to a variety of influences or powers, one of which is the sin-producing sarx. The updated NIV uses “flesh” as the translation in many places where it is important for readers to decide for themselves from the context whether one or both of these uses of sarx is present.