Yesterday I preached on 1 John 2:2, addressing the doctrine of propitiation and how a proper understanding of the cross cultivates humility and kills hubris. If you missed it you can listen to it here. Below are some helpful resources for you who want to dig deeper into the theology of Jesus' atonement.
These are small, but very good books on the atonement. For another great read that's free be sure to check out J.I. Packer's Saved By His Precious Blood. It's an introduction to John Owen's classic, The Death of Death in the Death of Christ.