How do we know that sin leads to physical illness?

While not every illness can be directly tied to a specific sin, the existence of sickness is a consequence of the fallen state of the world due to sin. In Psalm 6, the psalmist speaks of feeling weak and anguished, a reflection of the spiritual and physical toll that sin takes on humanity. We also see in Scripture that creation itself is affected by sin, leading to decay and illness. As believers, we acknowledge this reality and are encouraged to turn to God in our suffering, understanding that while sickness may stem from the effects of a sinful world, our ultimate healing and hope lie in Christ. The healing we seek therefore should always be approached in humility, recognizing the root of our condition and calling upon the Lord for mercy, rather than demanding justice.