Duff and I are writing a formation module on the Trinity. Who said we're not ambitious? Duff is the brains and I'm the legs. Fingers, too because I'll type. IOW, I'm the grunt. So Duff has assigned me to look up the documents from Vatican II. I did. I have 16. I don't think any of them are applicable. Maybe Dei Verbum can be used. That's the dogmatic Constitution on Divine Revelation; but I haven't read it, yet.
He also told me to write on Fatherhood in the Trinity. I'm glad. I'm very comfortable with the image of God as a Father. And I can find lots of scripture to quote God as Father:
Phil. 1:2 God our Father Sirach 23: 1, 4 Lord, Father, and God
and think of all the times Jesus prayed to the Father:
Matt. 6: 9-13 The Lord's Prayer Luke 6: 36 Be merciful as your Father
and all of John 17 is a prayer addressed to the Father.
Jesus also taught about the Father by way of parables:
Luke 15: 11-12 Prodigal Son Matt. 18: 23-35 Unforgiving servant.
And don't forget Jesus as the snippy adolescent who told His mother that He must be about His Father's business. (Nevermind what Mary and Joseph must have said and did--that's for another time.) Make note that even at this age, Jesus knows that He came to do the work of His Father.
Another good one is James 1:17, "Every good endowment and every perfect gift is from above, coming down from the Father of lights with whom there is no variation or shadow due to change." St. James tells us that God the Father is the source of all good things, and that's why I love God as Father.