So if Trinity Sunday isn't an interruption, what is it?
The Old Testament shows us God the Father. The New Testament shows us Jesus. And Jesus explains (repeatedly) his relationship with God the Father. So far so good.
Then the Holy Spirit shows up.
If we think of Pentecost as nothing but part of the whole Easter-Ascension-Pentecost thing, it can make the Holy Spirit seem kind of random.
But there's more to Pentecost than just its place as part of the Easter season. And the Holy Spirit is anything but random.
Making this clear? It’s one of the reasons for Trinity Sunday.
More on this tomorrow.