The evangelical counsels of poverty, chastity and obedience, he said, "strengthen faith, hope and charity," and bring people closer to God.
"This profound connection to the Lord, which must be the overriding and defining element of your existence, will renew your bond to him and will have a positive influence on your particular presence and form of apostolate," he said.
Pope Benedict told religious that they will be "credible witnesses for the church and the world today" through their charisms, their faithfulness to church teaching and witness to the faith.
He said he hoped the Year of Faith that starts in October would be a fruitful time for inner renewal, which is always needed, and for growing closer to God.
The Congregation for Institutes of Consecrated Life and Societies of Apostolic Life, he said, will help promote and make suggestions for the special year "so that all consecrated men and women will pursue, with enthusiasm, new evangelization."