How do we know that sin desires battle within all people?

The struggle between sinful desires and the influence of the Holy Spirit is a common theme found in Scripture. In Galatians 5:17, Paul writes, 'For the flesh desires what is contrary to the Spirit, and the Spirit what is contrary to the flesh.' This dual nature—wherein one is faced with the temptation of sin while simultaneously receiving guidance from the Holy Spirit—proves that the battle against sin is universal among believers. James reinforces this notion by addressing 'your desires that battle within you' (James 4:1), affirming that every Christian contends with a sinful nature that desires to lead them astray. Recognizing this inner conflict serves as an important reminder of our reliance on God's grace to aid us in the ongoing war against sin and to affirm that the presence of such a struggle is evidence of genuine faith.