Christian angelic hierarchy

The most influential Christian angelic hierarchy was that put forward by Pseudo-Dionysius the Areopagite in the 4th or 5th century in his book De Coelesti Hierarchia (On the Celestial Hierarchy). During the Middle Ages, many schemes were proposed, some drawing on and expanding on Pseudo-Dionysius, others suggesting completely different classifications. According to medieval Christian theologians, the angels are organized into several orders, or "Angelic Choirs".

Pseudo-Dionysius (On the Celestial Hierarchy) and Thomas Aquinas (Summa Theologica) drew on passages from the New Testament, specifically Ephesians 1:21 and Colossians 1:16, to develop a schema of three Hierarchies, Spheres or Triads of angels, with each Hierarchy containing three Orders or Choirs. Although both authors drew on the New Testament, the Biblical canon is relatively silent on the subject, and these hierarchies are considered less definitive than biblical material.

The first sphere angels serve as the heavenly servants of God the Son incarnated.

Seraphim (singular "Seraph") literally translated "burning ones", the word seraph is normally a synonym for serpents when used in the Hebrew Bible. Mentioned in Isaiah 6:1-7, Seraphim are the highest angelic class and they serve as the caretakers of God's throne and continuously shout praises: "Holy, holy, holy is the Lord of hosts; the whole earth is full of his glory!" According to Isaiah 6:1-8, the Seraphim are described as fiery six-winged beings; with two wings they cover their faces, with another two they cover their feet, and the last two they use to fly.

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