Angels are spirit beings, created by God. Only three angels are referred to by name in the Bible—Michael, Gabriel, and Satan.
There are many ranks and divisions—God's angels are under His authority and they are ministers for humans. Satan had a high position in heaven, but now he is leader of evil spirits.
Angels were created to serve the Creator. They have many jobs to do: 1) they praise and worship God; 2) they bring messages from God to man; 3) they provide for God's people; 4) they protect God's people; 5) they do God's will, and 6) they punish God's enemies, including Satan.
Their origin and nature
They are spirits — Heb 1:14
They were created by God — Ps 148:2, 5; Col 1:16
They were created early in creation — Job 38:6-7
They were created good — Gen 1:31
They are not to be worshiped — Col 2:18; Rev 19:10
They do not marry or die — Lk 20:35-36
Some angels rebelled against God — 2Pet 2:4
Names and ranks of good angels
Michael — Dan 12:1; Jude 9; Rev 12:7
Gabriel — Dan 9:21; Lk 1:19, 26
Archangels — 1Th 4:16
Seraphs — Isa 6:2
Cherubim — Eze 10:1-3
Rulers and authorities — Eph 3:10; Col 1:16
Thrones and powers — Col 1:16
There are numerous angels — Rev 5:11
Duties of good angels
General duties
They revealed the law — Acts 7:38; Gal 3:19; Heb 2:2
They bring messages from God — Zech 1:14-17; Acts 10:3-6
They praise and worship God — Heb 1:6; Rev 5:11-12
They provide for God's people — 1Kgs 19:5-8; Mt 4:11; Heb 1:14
They protect God's people — Ps 91:11; Dan 6:22; Acts 12:7-10
Some serve as guardian angels — Mt 18:10; Acts 12:15
They give guidance to God's people — Acts 8:26; 27:23-24
They interpret God's will — Dan 7:16; Zech 1:9,13-14
They carry out God's will — Num 22:22; Ps 103:20-21; Mt 28:2