Heidelberg Catechism, Lord’s Day 20
[Could you imagine a better question for Pentecost Sunday than this? It's almost like they planned it that way. "What do you believe concerning the Holy Spirit?" And the answer is not just that the Spirit is eternal God, but that I have been given him forever, to make me share with Christ and all his benefits. Happy Pentecost, indeed!]
Q53. What do you believe
concerning “the Holy Spirit”?
A53. First, that the Spirit, with the Father and the Son,
is eternal God.
Second, that the Spirit is given also to me,
so that, through true faith,
he makes me share in Christ and all his benefits,
and will remain with me forever.