Most Holy Trinity
Every time we say, "In the name of the Father, and of the Son, and of the Holy Spirit," we are proclaiming that our God is a Trinity - that from all time our God has been a relationship of love: 3 distinct Persons, fully united as 1 God. And this God made us - humanity - to share in His love! But to know God as Trinity is not something we can describe with words alone, it is something that has to be experienced to be believed!
In our baptism we received the same Holy Spirit that the disciples received 2,000 years ago. By our Confirmation we were sealed and strengthened in that Holy Spirit. So why don't we see the miracles and wonders that the presence of the Spirit brings, like those in our 1st reading? In order for the power of the Spirit (which is already within us) to be unlocked and unleashed through our lives, we have to be able to say, in all areas of our life, with our whole heart, "Jesus is Lord!" The more we can say that, the more the Holy Spirit can come out with power!