In his sleep at Bethel, Jacob had a vision:
There was a ladder set up on the earth, and the top of it reached to heaven; and behold, the angels of God were ascending and descending on it! And behold, the LORD stood above it and said, "I am the LORD, the God of Abraham your father and the God of Isaac. (Genesis 28:12-13b)
In today's Gospel for the feast of the Archangels, Jesus identifies himself with the Ladder:
And he said to Nathanael, "Truly, truly, I say to you, you will see heaven opened, and the angels of God ascending and descending upon the Son of man." (John 1:50-51)
Such a simple expression of fundamental Christianity! What connects the utterly other, completely transcendent and unknowable God to our world of time and history and mundane matter? The human life of Jesus of Nazareth is the ladder that connects heaven and earth, on which ascend and descend the messengers and messages of God that we call the angels.
Christianity is nothing more than the grateful response to God's bridging of the gap between the transcendent realm of heaven and our world of time and matter in Jesus Christ. It's why we sing in the Easter Exsultet,
"Night truly blest, when Heaven is wedded to earth, and man is reconciled with God."