By the three first petitions, we are strengthened in faith, filled with hope, and set aflame by charity. Being creatures and still sinners, we have to petition for us, for that "us" bound by the world and history, which we offer to the boundless love of God. For through the name of his Christ and the reign of his Holy Spirit, our Father accomplishes his plan of salvation, for us and for the whole world.
Source: Catechism of the Catholic Church (Vatican.va)