God’s wrath is the thing to fear most.
Angels, being in communion with God can be assumed to be in perfect accord with God’s disposition about human affairs and are given special roles as executors of God’s messages and His will. It is said a single Angel is empowered by God with the powers to utterly destroy all of Creation and if it were not for Jesus’ Divine Mercy that appeases God’s Wrath would be inclined to petition God for permission to utterly destroy all gravely evil beings. Their pure and powerful angelic nature is outraged by humankind’s grave offenses but they know it is God’s will to glorify His Son by playing out Divine Plan to its objective end. God’s Plan is working toward a specific objective that has assurances of attaining a Greater Good through the infinite merits of Jesus won on the cross. Thank God!
Note that the third secret of Fatima, entrusted to Sr. Lucia, reveals an angel flashing a flaming sword towards mankind. The angel threatens to set the world on fire, and shouts “Penance! Penance!.”
In one of St. Faustina’s Divine Mercy visions she recorded in her diary on Sept. 13, 1935 we have:
“I saw an Angel, the executor of God’s wrath… about to strike the earth…I began to beg God earnestly for the world with words which I heard interiorly. As I prayed in this way, I saw the Angel’s helplessness, and he could not carry out the just punishment…”
Some of these may be literalistic mechanisms but I personally think that the pure and holy nature of Angels is such that these private revelations reflect a genuine supernatural angelic outrage over the grave blasphemies and sins of humanity at large.
James