What is the role of the Holy Spirit in the Roman Catholic church? What is the role of the Holy Spirit in the Roman Catholic church? When I search online, I mostly find stuff about filioque. But I want to know specifically what he does. What is his role? How does he affect our salvation?
The theology of the Holy Spirit (or Holy Ghost - the two terms mean the same thing) is a huge subject. This article gives a systematic explanation from the Catholic point of view.

Catholic theology of the Holy Spirit is very little different from general Protestant or Orthodox theology of the Holy Spirit, with a few notable exceptions, which I will attempt to list:


It is generally accepted that one of the roles of the Holy Spirit is to guide the interpretation of the Scriptures. There is variation in how the Spirit is believed to do this. Protestants believe the Spirit does this either through Christians in general, or through the community of the church. Catholics believe that the Spirit does this through the church and its structures - specifically the Catholic church.
Catholics would fall in with mainstream Protestants (but not Pentecostals) in believing that the supernatural gifts of the Spirit (tongues, healings etc.) are not given to all Christians, and are relatively rare.
One important but obscure belief specific to Catholics is the belief that the Holy Spirit proceeds from both the God the Father and the Son. This beliefs is notable only because it is the nominal cause of the split between the Catholic and Orthodox churches.


There may be others that I am unaware of.