Advent, like Lent, is traditionally a time of increased prayer, fasting, almsgiving, and Bible reading. The Church doesn’t do these things because we need to prove anything to God or get His attention. We do these things because we need to train both our minds and our flesh. We are training to resist temptations and for times of persecution. The Apology to the Augsburg Confession quotes this coming Sunday’s Gospel (Advent 2, St. Luke 21:25-36) to prove that Christ calls upon us to engage in voluntary and necessary spiritual exercises of fear and faith.

With regard to the mortification of the flesh and discipline of the flesh, we teach—just as the Confession states—that a genuine rather than a counterfeit death takes place through the cross and afflictions by which God exercises us. In these it is necessary to submit to the will of God, as Paul says [Rom. 12:1], “Present your bodies as sacrifices.…” These are the spiritual exercises of fear and faith. Alongside this true putting to death, which takes place through the cross, a voluntary and necessary kind of exercise also exists, about which Christ says [Luke 21:34], “Be on guard so that your hearts are not weighed down with dissipation,” and Paul [1 Cor. 9:27] says, “but I punish my body and enslave it …” We should undertake these exercises not because they are devotional exercises that justify but as restraints on our flesh, lest satiety overcome us and render us complacent and lazy. This results in people indulging the flesh and catering to its desires. Such diligence must be constant, because God constantly commands it. (Ap. 45-47, Kolb-Wengert)