The sin nature is what the New Testament refers to as “sin in the flesh” (Rom. 8:3). Adam was given one command to obey. Romans 5:12 states that the sin nature entered the world as the result of Adam’s one act of disobedience. This newly acquired nature brought death with itself, making all the children of Adam mortal through its possession. All human beings are born into this world with this sinful nature, all under its mastery and power, all motivated to disobedience to God, having no possibility of pleasing Him (Rom. 8:4-8).
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