It was in this post-conciliar period of reflection—between 1979 and 1983—that Congar wrote Je crois en l’Esprit Saint (French for "I Believe in the Holy Spirit"). He was 75 years old, synthesizing a lifetime of biblical exegesis, patristic study, and ecumenical dialogue into a single work.
If that works for you, here is an original overview: Yves Congar I Believe In The Holy Spirit.pdf