Angels are guardians of God’s people: For he will command his angels concerning you to guard you in all your ways ~ Psalm 91:11. The Bible says that God sends his angels to watch over us. Someone has said that angels may play zone defense rather than man-to-man defense as they protect people from harm.
In Matthew 18:10 : I tell you that their angels in heaven always see the face of my Father in heaven, Jesus speaks of children’s angels, but does not say that each believer has just one guardian angel.
Although angels can take on different forms, including human forms, they are spiritual beings (without flesh and bones) that God created during the six days of creation. Shortly after creation, some angels rebelled against God and became evil angels or demons: God did not spare angels when they sinned, but sent them to hell ~ 2 Peter 2:4. The chief of the evil angels is the devil, Satan. Please note that angels are not the spirits of deceased people but are personal beings that God created at the beginning of time.
Angels serve God in various ways. Our Heavenly Father sends angels to watch over his people. He has used angels as messengers at key times in history and they continue to play a part in controlling the forces of evil that seek to destroy God’s church. Are not all angels ministering spirits sent to serve those who will inherit salvation? ~ Hebrews 1:14
God’s angels will also accompany Jesus Christ when he returns at the end of the world: When the Son of Man comes in his glory, and all the angels with him, he will sit on his glorious throne. ~ Matthew 25:31.