Some thoughts by Pope Benedict XVI on evangelization:
“How many people also in our time are in search of God, in search of Jesus and of his Church, in search of divine mercy, and are waiting for a “sign” that will touch their minds and their hearts! Today, as then, the Evangelist reminds 
us that the only “sign” is Jesus raised on the cross: Jesus who died and rose is the absolutely sufficient sign. Through him we can understand the truth about life and obtain salvation.”
“[Evangelization] is not something optional, but the very vocation of the People of God, a duty that corresponds to it by the command of the Lord Jesus Christ himself”
“One of the promising indications of a renewal in the Church’s missionary consciousness in recent decades, has been the growing desire of many lay men and women […] to cooperate generously in the ‘missio ad gentes.’ As Vatican Council II stressed, the work of evangelization is a fundamental duty incumbent upon the whole People of God.”