Within the Christian angelic hierarchy, there are three total spheres of angels. The first sphere of God's angels or celestial beings, watch over and guard God's seat of power, or his throne. Some scripture even refers to this first sphere as consisting of angelic beings that serve as God's heavenly counselors. The Biblical foundation for the sphere can be traced to the New Testament scripture Colossians Chapter 1 verse 16 and Ephesians Chapter 1 verse 21. It is not thought that the sphere itself is an actual spiritual construct of any kind, it is more of a classification system that was created to distinguish certain ranks of angels from one another. There are many Renaissance paintings featuring the three spheres, such as the famous Francesco Botticini painting known as The Assumption of the Virgin. In this one specific painting, the three spheres look similar to a large spiral staircase leading up to heaven, with God himself featured at the very top.
There are three separate ranks of angels within the first angelic sphere, with the first being the six winged Seraphim. The Seraphim are the highest order of angels within the entire Christian angelic hierarchy, standing above all other classes of celestial beings. They were first introduced to the world in the Old Testament scripture of Isaiah Chapter 6 verses 1 through 7, where they are described as the direct watchmen over God's throne. According to this scripture, the Seraphim are locked in internal song, singing "Holy, holy, holy is the Lord of hosts. All of the earth is filled with His glory". It is also mentioned within this same Biblical scripture that the Seraphim angels radiate a bright white light, and that no human being can look at them. This light shining out of them is described as an eternal love for God that burns without end. Hence the Hebrew name Seraphim means "the burning ones", however the origin of this name may predate Hebrew.
The second rank of angels within the first sphere, are the Cherubim, mentioned throughout the Bible in Genesis Chapter 3 verse 24, Ezekiel Chapter 10 verses 17 through 20 and Chapter 28 verses 14 through 16, as well as 1 Kings Chapter 6 verses 23 through 28. The Cherubim are often confused with the Seraphim, however they are a completely separate class of angels. In Biblical scripture, it is taught that they are near the throne of God, and that they watch over the stars and light. Each of the Cherubim have four separate faces, one of an eagle, one of a man, one of an ox, and one of a lion. Their true face is thought to be that of the ox, as described in Ezekiel chapter 10. Apart from their four faces, the Cherubim have four wings, one set with which they use to cover their faces, and the other set they use to cover their feet. There has been some dispute over the centuries as to whether or not the Cherubim belong in the first sphere or third sphere.
The third class of angels within the first angelic sphere, are the Thrones. They are also often referred to as the Elders, Erelim, or Ophanim. These celestial beings are first mentioned in the New Testament in Colossians Chapter 1 verse 16. Here they are described as living entities that symbolize God's authority and reign. While many angels in the Bible are described as having attributes of humans or animals, these creatures are giant wheels. In Daniel Chapter 7 verse 9, they are said to be wheels within wheels, and having rims that are covered with hundreds of eyes. These Ophanim are thought to be closely linked to the Cherubim. In Ezekiel Chapter 10 verse 17, it is said that when the Ophanim move, so do the Cherubim, for the Cherubim are inside of these wheels. Modern scholars have interpreted Biblical scripture as meaning that the Thrones are extremely large angelic beings as compared to the Seraphim and Cherubim.