Answer
Much of the book of Isaiah is record of God working with a sinful people to give them a confident hope of future redemption. The book of Isaiah records the events surrounding Israel and Judah, from Isaiah’s calling in 740 BC, “the year that King Uzziah died” (Isaiah 6:1), to sometime after the Assyrian King Sennacherib died (681 BC). During this time, Assyria invaded and conquered the northern kingdom of Israel (722 BC) and attempted to conquer the southern kingdom of Judah. Babylon then conquered Assyria, and an invasion of Judah was coming. These calamities were a result of God’s judgment on a sinful people (Isaiah 1; see Deuteronomy 28:62–68).
God describes the sin of Judah as being “as scarlet” and “red like crimson” in Isaiah 1:18 (KJV). Scarlet often represented wealth and royalty (cf. Jeremiah 4:30; Matthew 27:28), but in the context of Isaiah 1:18, scarlet and crimson represent contamination, a deep stain of sin. To achieve a scarlet-colored fabric, a material would be soaked in a scarlet dye. This staining process illustrates how sin had permeated the fabric of society; the sins of God’s people were “as scarlet.” The stain of sin had infused their very hearts.
This concept of the “stains” of sin is seen elsewhere in Scripture (Jeremiah 2:22; 1 Timothy 6:14; 1 Corinthians 6:11). Sin is often depicted as a stain, and righteousness is depicted as pure white. In Revelation 7, for example, a great multitude of people gather around God’s throne, all wearing white robes. An angel identifies the people: “These are they who have come out of the great tribulation; they have washed their robes and made them white in the blood of the Lamb.” It is the blood of the Lamb—Jesus Christ—that is required to take away the stain of sin and make one righteous (see John 1:29).
All of us are born stained and sinful (Romans 5:12; Ephesians 2:1–3). We are all in need of cleansing. What can wash away our sin, which is as scarlet and red as crimson? By the grace of God, we can be cleansed through faith in Jesus Christ. Peter puts the good news this way: “For you know that it was not with perishable things such as silver or gold that you were redeemed from the empty way of life handed down to you from your ancestors, but with the precious blood of Christ, a lamb without blemish or defect. He was chosen before the creation of the world, but was revealed in these last times for your sake. Through him you believe in God, who raised him from the dead and glorified him, and so your faith and hope are in God” (1 Peter 1:18–20).
Sin is like a crimson stain, indicative of blood guilt. But, to the eternal praise of our Lord Jesus Christ, we can be cleansed of that stain: “Though your sins are like scarlet, they shall be as white as snow; though they are red as crimson, they shall be like wool” (Isaiah 1:18).