What does Isaiah 9:19 mean?
Isaiah described wickedness as a fire that begins with consuming smaller, nearby fuel before becoming more aggressive. It leaps from kindling to thickets to trees. Eventually, the forest is ablaze (Isaiah 9:18).The Lord can use even this "fire" for His own purposes. He brings judgment on His own people in response to their stubborn, unrepentant wickedness. The land is scorched from fires with two sources: the burning of wickedness and the flames of the Lord's wrath toward that sin. In the end, human lives become the fuel for both. Sin devours those who practice it. This is the natural consequence of letting sinfulness run your life. In addition, the Lord steps in to judge those who continue to spread the flames of sin to others.
A common question applied to sin is "who will this hurt?" Isaiah's answer is that sin spreads. It will burn us and then those near us. Then, apart from God's mercy and forgiveness through faith in Christ, we will be engulfed by the wrath of the Lord. Sin never just "infects" one person.
