Horus, Osiris, Isis 2
A 20th dynasty (see: supreme god timeline) depiction of Horus, Osiris (who typically has green skin), and Isis statue (Ѻ); the platform of Osiris, being a lapis lazuli pillar, representative of the chest that Set trapped him in and or the djed pillar (see: Passion of Osiris), held at the Louvre, Paris. (Ѻ)
In Egyptian mythology, Horus, hieroglyph:Heru H, or "Heru", hieroglyph Heru (hieroglyph), “Harpocrates” (Alexander, 330BC), (Ѻ) "Orus" (Plutarch, 100AD; Taylor, 1829), symbolized by is an ancient falcon-headed god, or "hawk god" (Budge, 1904), of Egypt, originally, in the predynastic era (before 3,100BC), thought of as the "height of the heavens" and ranked as the oldest god of Egypt, who became re-conceptualized in the Dynastic era, via the Heliopolis recension (2,500BC), as the son of Osiris and Isis.

Form
The following shows three images (Ѻ) of Horus, namely Left: Statue of Horus as a falcon (temple of Horus, Edfu; Ptolemaic Era); middle: Horus as a falcon-headed man (temple of Horus, Edfu; Ptolemaic Era); right: lanner falcon, Falco biarmicus, which is what the Egyptians thought Horus had his animal god form as:

Horus (three images)

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Eye of Horus
See main: Eye of Horus: See also: Eye of Ra
The following, from the Ani-version of the Egyptian Book of the Dead, shows Horus labeled with the hieroglyph "Horus the eyeless":

Horus the eyeless (hieroglyph)

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Horus head (sculpture)
A bust (Ѻ) of Horus.

Child Horus
In 1907, Gerald Massey (Ѻ), and following him Tom Harpur (2004), were referring to the "child Horus" as "Iusa" or "Iu-em-hetep"; and example of which, given by Harpur, is as follows: [7]

“According to Herodotus, the Egyptian Jesus, known as Iu-em-hetep [child Horus] was one of the eight great gods who were described in the papyri as having existed almost twenty-thousand years ago.”

Harpur, to note, footnotes the name Iu-em-hetep, incorrectly, as: “who the Egyptologists call Imhotep”, which is a real person.

Heliopolis
Horus, according to the Heliopolis recension (see: Heliopolis creation myth), was morphed or merged so as to become the son of Osiris and Isis.

Etymology
Horus originated, supposedly, as a totem of an Upper Egyptian nome which at the opening of the dynastic epoch is believed, according to some historians, to have conquered Lower Egypt and brought about a union of Egypt.

In circa 2,800BC, the priests of Heliopolis, according to Jon White (1963), merged the worship of the so-called historical Horus with the legendary Horus, son of Osiris.

Horus (sun disc), Osiris (tamarisk tree), Jesus (halo and evergreen tree)
A depiction of how the myth of Horus carrying the sun (or sun disc) on his head, and myth of Osiris dying and being reborn as an evergreen tree (tamarisk tree), became merged into the monotheistically reformulated myth of Jesus being born under or near a Christmas tree with a halo on his head.
Osiris-Horus | Jesus
In c.100 to 500AD, during the Roman recension, the joint god Osiris-Horus became rescripted, monotheistically, into the man god Jesus.

In 1877, English Egyptologist William Cooper, in his The Horus Myth in its Relation to Christianity, attempted to stitch out the roots of Jesus Christ and Christianity in terms of the Horus. [2]

Quotes
The following are related quotes:

“The loadstone is called, by the Egyptians, the ‘bone of Horus’, as iron is the ‘bone of Typho [Set].”
— Manetho (c.300BC) [5]

“The Egyptians, in fact, have a tradition that Hermes [Thoth] had thin arms and big elbows, that Typhon [Set] was red in complexion, Horus white, and Osiris dark.”
— Plutarch (100AD), On Isis and Osiris (pg. 55)

Horus is the oldest god of all / Horus is the oldest of all Egyptian gods.”
Wallis Budge (1904), The Gods of Egypt, Volume One [4]

“Even after political unification, in c.3100BC, there were always two Egypts: Lower Egypt (delta religion of Nile), represented by Seth, and Upper Egypt (from Memphis at the apex of the delta and along the river to its upper reaches at Aswan), represented by Horus.”
— Scott Littleton (2002), Mythology [3]

See also
Horus Gilgamesh
Joshua 10:13

References
1. White, Joh Manchip. (1963). Everyday Life in Ancient Egypt (pg. 113). Dover, 2002.
2. Cooper, William. (1877). The Horus Myth in its Relation to Christianity. Hardwick & Bogue.
3. Littleton, C. Scott. (2002). Mythology: the Illustrated Anthology of World Myth and Storytelling (pg. 11). Thunder Bay Press.
4. Budge, Wallis. (1904). The Gods of the Egyptians, Volume One (pgs. 58, 349). Dover, 1969.
5. (a) Budge, Wallis. (1904). The Gods of the Egyptians, Volume Two (pg. 246). Dover, 1969.
(b) Manetho – Wikipedia.
6. Harpur, Tom. (2004). The Pagan Christ (pg. 34; Osiris/Dionysus commonalities, pg. 38). Thomas Allan Publishers.
7. (a) Massey, Gerald. (1907). Ancient Egypt: The Light of the World: a Work of Reclamation and Restitution in Twelve Books, Volume Two (Iu-em-hetep, 42+ pgs; esp. pgs. 675, 927). T. Fisher Unwin.
(b) Harpur, Tom. (2004). The Pagan Christ (pgs. 37-38). Thomas Allan Publishers.

Further reading
● Griffiths, John G. (1960). The Conflict of Horus and Seth: from Egyptian and classical sources: a study in ancient mythology. Liverpool University.

External links
Horus – Wikipedia.
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