In the next section of the third and final part of Verbum Domini, the Holy Father writes about our commitment in the world. Pope Benedict points out that "we tend to halt in a superficial way before the importance of the passing moment, as if it had nothing to do with the future. The Gospel, on the other hand, reminds us that every moment of our life is important and must be lived intensely."
Each moment is a Christian moment. Each moment should not just be lived by lived intensely.
We are not meant to hide from the world in our house or community but to live in it.The Pope focuses in particular on our interactions with others in need, both individuals and society as a whole. "(I)t is not the direct task of the Church to create a more just society, although she does have the right and duty to intervene on ethical and moral issues related to the good of individuals and peoples." Whatever we do to each other, we do to Christ. (...) This includes caring for those who suffer and for victims of selfishness, promoting reconciliation (whether with one person, a branch of your family tree, or an entire social group), and promoting human dignity (often against the efforts of those who don't recognize their own).
The Synod recommends that any of us involved in political and social activity "receive a suitable formation in the principles of the Church's social teaching." The USCCB provides a short summary of the Seven Principles of Catholic Social Teaching. This is a good place to start.
For more than a summary treatment, consider Pope Leo XIII's Encyclical Rerum Novarum, from 1891, which touches on issues like working conditions, unionization, and capitalism. Also consider the more recent apostolic exhortation Ecclesia in America, in which Blessed John Paul II discusses how Christ is encountered in modern America.