"An Exorcist Explains the Demonic: The Antics of Satan and His Army of Fallen Angels" by Fr. Gabriele Amorth.

We experience suffering and pain here on Earth. Men and angels are being tested in fidelity to God’s laws i.e. fallen angels failing to be faithful to His laws.

The connection of Christ as Our Savior comes with His birth, death, and resurrection.

Through Our Blessed Mother's Immaculate Conception, Christ is born w/o sin. As a result, he becomes the Son of God. Later, His death leads to His resurrection, which is the cause for eternal salvation. One of the three victories for Christ's victory. The other two are reuniting body and soul in the Last Judgment and opening the door to Heaven.