Alexandr Korol

In the 4th century, Christians, borrowing the nimb as a sign of supreme authority from imperial iconography, began regularly depicting their God with it. Only in the 5th–6th centuries did nimbs become a permanent attribute of Christ, the Mother of God, and other saints. In Christian iconography, the nimb became associated with images of the hypostases of the Holy Trinity, angels, the Mother of God, and saints; it often also accompanied the Lamb of God and figures of animals serving as symbols of the four evangelists (see tetramorph). For some icons, special types of nimbs were established. For example, the face of God the Father was placed within a nimb that initially had the shape of a triangle, then the shape of a six-pointed star formed by two equilateral triangles. The Holy Spirit (in the form of a dove) and the All-Seeing Eye were sometimes depicted with a triangular nimb. Christian iconography assigned to the Savior predominantly the “crossed” nimb — that is, a round disk with an equal-armed cross inscribed inside it, with the lower end hidden behind the head. This same nimb was given to symbolic images of Christ, the Good Shepherd, and the Lamb of God, as well as, in some cases, the Holy Spirit. Later, the decoration of such a nimb replaced the cross with three lines or three bundles of rays radiating from the center of the disk like spokes. The Mother of God is depicted with a circular nimb decorated with twelve stars, a diadem, or a radiant crown. Angels and saints are given a simple, round nimb, which old painters gilded when depicting apostles, martyrs, and generally New Testament saints, while prophets and patriarchs were depicted with silver nimbs.

Orthodoxy
In Orthodoxy, on Greek and Russian Orthodox icons, inscriptions are often placed on or near the nimbs. On the nimb of Jesus Christ, there are three letters Ὀ (ὁ), ὤ (ὤ), Ν (ν): ancient Greek ὁ ὤν is a noun meaning “The Existing One,” derived from the ancient Greek verb εἰμί — to be. “The Existing One” means the eternally existing one — this is one of the names that refers exclusively to God the Creator and does not apply to any of the other created beings who have a beginning. Next to Christ’s nimb is the inscription ancient Greek Ι ҃ Σ Χ ҃ Σ or Ι ҃C Χ ҃C → Ἰησοῦς Χριστός → Jesus Christ. Thus, the inscription on Christ’s nimb means that Jesus Christ is The Existing One, that is, the true and eternal God without beginning. The three letters are usually placed on the image of the Cross