Contemplative prayer is silence, the "symbol of the world to come" or "silent love." Words in this kind of prayer are not speeches; they are like kindling that feeds the fire of love. In this silence, unbearable to the "outer" man, the Father speaks to us his incarnate Word, who suffered, died, and rose; in this silence the Spirit of adoption enables us to share in the prayer of Jesus.
Source: Catechism of the Catholic Church (Vatican.va)