Have you ever wondered what it would take to kill an angel? Well, the answer is that angels don't have bodies so nothing can kill them. Likewise, they never get sick and never grow old. God created countless angels — pure spirits without bodies. This means angels are neither male nor female. They also can't taste ice cream. Each angel is, however, what's called a person having the ability to think and choose, to know and love.
The Catechism of the Catholic Church teaches in paragraph 327 that God first made spiritual angels at the "beginning of time" before creating man. Catholics must believe angels exist. This Catechism calls this "a truth of faith."
The word angel is from the Greek word angelos, which means messenger. Angels are God's messengers, who do His will. The Old Testament speaks of angels doing all sorts of things. Paragraph 332 of the Catechism recalls that angels "protected Lot ... stayed Abraham's hand ... led the People of God ... announced births ... and assisted the prophets."
Angels weren't busy just in the Old Testament. Hebrews 1:14 calls angels "ministering spirits, sent to minister for them, who shall receive the inheritance of salvation." Paragraph 333 of the Catechism focuses on angels in New Testament. Here it says they announced the birth of Christ, sang at His birth and strengthened Him in the garden of Gethsemane. The Catechism also foretells that angels "will be present at Christ's return, which they will announce, to serve at His judgment." They're even at every Mass, according to St. Paul in 1 Corinthians 11:10.
Angels are what theologians call preternatural beings, meaning they can do things men can't. They're really smart and can also manipulate energy and matter in ways man doesn't understand. Angels are not, however, supernatural. They can't create stuff like God can or know the future unless God reveals it to them.
Saint Thomas Aquinas is called the Angelic Doctor because of how much he wrote about the angels in the Summa Theologica.
Become familiar with our celestial companions in season one of Church Militant's Premium show Armor of God—Angels & the Immaterial World.