In Brief CCC 804
© Libreria Editrice Vaticana Source: vatican.va
One enters into the People of God by faith and Baptism. "All men are called to belong to the new People of God" (LG 13), so that, in Christ, "men may form one family and one People of God" (AG 1).
Read the full chapter 3. I Believe in the Holy Spirit ¶683–1065