Roman Catechism 38.32

Chapter 38 — Part IV: Prayer — The Fourth Petition: Give Us This Day Our Daily Bread

Section 32. "us" — But why say give us, in the plural number, and not give me? Because it is the duty of Christian charity that each individual be not solicitous for himself alone, but that he be also active in the cause of his neighbour; and that, while he attends to his own interests, he forget not the interests of others.