John Wesley addresses the complex relationship between sin and believers, emphasizing that while those in Christ are new creations, sin still remains in their nature. He argues that even justified believers must contend with an evil nature, as evidenced by Scripture and the experiences of early Christians. Wesley warns against the dangerous belief that true believers are entirely free from sin, asserting that this notion is both new and contrary to biblical teaching. He encourages believers to recognize the ongoing struggle against sin and to actively resist it, maintaining their faith and reliance on God's grace. Ultimately, Wesley calls for vigilance and perseverance in the Christian walk, acknowledging the dual nature of believers who are both justified and still wrestling with sin.