And he is the atoning sacrifice{"atoning sacrifice" is from the Greek "hilasmos," an appeasing, propitiating, or the means of appeasement or propitiation-- the sacrifice that turns away God's wrath because of our sin.} for our sins, and not for ours only, but also for the whole world.
From these verses we learn that a poor backslider need not despair of again finding mercy; this passage holds out sufficient encouragement for his hope. There is scarcely another such in the Bible, and why? That sinners might not presume on the mercy of God. And why this one? That no backslider might utterly despair. Here, then, is a guard against presumption on the one hand, and despondency on the other.