Jesus The "Sun" of God

Malachi 4:2 "...the sun of righteousness will rise with healing in its rays. And you will go out and frolic like well-fed calves."
Psalm 84:11 "For the Lord God is a sun and shield"

The evidence of sun worship is abundant in the old testament. The Israelite people were warned and condemned of its practice in many verses.

Deuteronomy 4:19 "And when you look up to the sky and see the sun, the moon and the stars—all the heavenly array—do not be enticed into bowing down to them and worshiping things the Lord your God has apportioned to all the nations under heaven."

Deuteronomy 17:2-3 "...and contrary to my command has worshiped other gods, bowing down to them or to the sun or the moon or the stars in the sky,"

2 Kings 23:5 "He did away with the idolatrous priests appointed by the kings of Judah to burn incense on the high places of the towns of Judah and on those around Jerusalem—those who burned incense to Baal, to the sun and moon, to the constellations and to all the starry hosts."

Jeremiah 8:1-2 "They will be exposed to the sun and the moon and all the stars of the heavens, which they have loved and served and which they have followed and consulted and worshiped. They will not be gathered up or buried, but will be like dung lying on the ground."

Leading up to, during, and long after the time of Jesus, people worshiped the sun. 
The events that transpired in unifying the December 25th date of Jesus' birth directly is linked to Sol Invictus 
Solar Deity  "During the Roman Empire, a festival of the birth of the Unconquered Sun (or Dies Natalis Solis Invicti) was celebrated on the winter solstice—the "rebirth" of the sun—which occurred on December 25 of the Julian calendar. In late antiquity, the theological centrality of the sun in some Imperial religious systems suggest a form of a "solar monotheism". The religious commemorations on December 25 were replaced under Christian domination of the Empire with the birthday of Christ"
Sol Invictus and Christianity and Judaism "It was a custom of the Pagans to celebrate on the same 25 December the birthday of the Sun, at which they kindled lights in token of festivity. In these solemnities and revelries the Christians also took part. Accordingly when the doctors of the Church perceived that the Christians had a leaning to this festival, they took counsel and resolved that the true Nativity should be solemnised on that day."

During the Winter solstice or also December solstice which happens from December 20-22 each year, the sun in the northern hemisphere appears to disappear into the earth for 3 days. On or near the 25th of December after the Sun's ebbing presence seen by sun worshipers as a 'reversal', the sun appears again being "reborn". In essence, the Sun dies, is buried in the earth for 3 days, and then resurrected.

Orion's belt has 3 stars also known as "Three Kings", who point the way or "follow" the brightest star Sirius. Same as the 3 magi who follow the star to the birth of the "son". At the time of the winter solstice you have the 3 kings following the star Sirius to the birth of the "sun"

The Zodiac "is a circle of twelve 30° divisions of celestial longitude that are centered upon the ecliptic, the apparent path of the Sun across the celestial sphere over the course of the year."

Here we have the "Sun" as the central focal point around 12 signs. Jesus being the "Son" and focal point around his 12 disciples. Another thing to note is the 30 degrees, Jesus begins his ministry with his 12 disciples at the age of 30.

 
I could go on and elaborate in my own words just mirroring what is already out there. Instead I will post a site that from start to finish explains in great detail the mythology of the sun and how it has intertwines with Judaism/Christianity... Solarmythology

The site explains everything that Jesus did in correlation with the sun's movement across the Zodiac. From meeting John the Baptist, walking on water, the transfiguration, and so on.