Atonement is a very important concept that we see in the Old Testament. The animal sacrificial system, which is part of the Mosaic law, taught that sins must be atoned for. And so this all the sacrificial language, Jesus didn't introduce it. He's the lamb that takes away the sins of the world. That's why you have verses in 1 John, verse 2, that we have an advocate with the Father. We're not doing anything. God unilaterally is making a promise to his people.