The origin of decorated trees can be traced to Germany and to Egypt before that. These trees were not recognized as a Christmas decoration but in fact were worshiped as false gods. People thought the trees had some type of mystical powers and were very afraid of them.

Origin of the Christmas Tree

Cult worshipers sanctioned Christmas trees and brought them into their homes to decorate them." Just as early Christians recruited Roman pagans by associating Christmas with the Saturnalia, so too worshippers of the Asheira cult and its offshoots were recruited by the Church sanctioning “Christmas Trees”.  Pagans had long worshiped trees in the forest, or brought them into their homes and decorated them, and this observance was adopted and painted with a Christian veneer by the Church (1). 

When Christians Began Bringing Decorated Trees into their homes

In spite of the fact that these decorated trees were known to have pagan origins and were frequently used in Pagan rituals, even Christians began bringing them into their homes during the 16th century.
"The fierce Vikings in Scandinavia thought that evergreens were the special plant of the sun god, Balder. Germany is credited with starting the Christmas tree tradition as we now know it in the 16th century when devout Christians brought decorated trees into their homes" (2).
Christmas trees have been used in Pagan, Catholic, and Christian ceremonies over the centuries  and if you research the history you will discover that people have made up their own idea's about the tree, some including a Pope have even refer to it as a symbol of Christ's birth, which it certainly is not. Nothing used in Pagan rituals can be associated with our Lord. The early church did not agree with the custom of decorated trees as they knew that this as a pagan custom where they would hang a tree branch and decorate it believing that this would bring them good crops and prosperity. "During the Roman celebration of the feast of Saturnalia, Pagans did decorate their houses with clippings of evergreen shrubs. They also decorated living trees with bits of metal and replicas of their God, Bacchus" (5).

Evergreen Trees worshiped as false Gods of life and fertility

"Evergreen trees were used as an idol to be worshiped in Germany as false gods such as the yule god or the resurrected sun god. They were commonly used during fertility worship because they were regarded as a phallic symbol which stemmed from the essence of life". ​ (3)
Protestant Christian reformer Martin Luther is accredited with putting the first lighted candles on an evergreen tree.
"According to the Encyclopedia Britannica, "The use of evergreen trees, wreaths, and garlands to symbolize eternal life was a custom of the ancient Egyptians, Chinese, and Hebrews. Tree worship was common among the pagan Europeans and survived their conversion to Christianity in the Scandinavian customs of decorating the house and barn with evergreens at the New Year to scare away the devil and of setting up a tree for the birds during Christmastime"(4).
Pagans in Europe used branches of evergreen fir trees to decorate their homes and brighten their spirits during the winter solstice.
Early Romans used evergreens to decorate their temples at the festival of Saturnalia, while ancient Egyptians used green palm rushes as part of their worship of the god Ra. "
​The idea of bringing the evergreen into the house represents fertility and new life in the darkness of winter, which was much more of the pagan themes," Dr Dominique Wilson from the University of Sydney said.
"That's also where the ideas of the holly and the ivy and the mistletoe come from because they're the few flowering plants at winter so therefore they hold special significance. "So the idea of bringing evergreens into the house started there and eventually that evolved into the Christmas tree" (6).

List of Bible Verses about decorated trees

The Lord Warns His people about worshiping false gods
Jeremiah 10
God and Idols ;
Hear what the LORD says to you, people of Israel. Jer. 10:1

This is what the LORD says: “Do not learn the ways of the nations or be terrified by signs in the heavens, though the nations are terrified by them. Jer. 10:2
The Lord describes a decorated tree cut from the forest that the people worshiped & feared and describes the tree's impotency
For the practices of the peoples are worthless; they cut a tree out of the forest, and a craftsman shapes it with his chisel. Jer. 10:3

They adorn it with silver and gold; they fasten it with hammer and nails so it will not totter. Jer. 10:4

Like a scarecrow in a cucumber field, their idols cannot speak; they must be carried because they cannot walk. Do not fear them;  they can do no harm nor can they do any good.” Jer. 10:5
​
Fear the Lord 
No one is like you, LORD; you are great, and your name is mighty in power. Jer. 10:6

Who should not fear you, King of the nations? This is your due. Among all the wise leaders of the nations and in all their kingdoms, there is no one like you. Jer. 10:7

The decorated tree is described as "senseless & foolish, worthless idols"
They are all senseless and foolish;  they are taught by worthless wooden idols. Jer. 10:8

Hammered silver is brought from Tarshish and gold from Uphaz. What the craftsman and goldsmith have made  is then dressed in blue and purple— all made by skilled workers. Jer. 10:9

The Lord is the true God and we really do not want to make Him angry
But the LORD is the true God; he is the living God, the eternal King. When he is angry, the earth trembles;  the nations cannot endure his wrath. Jer. 10:10

Warning from the Lord about these decorated trees
 “Tell them this: ‘These gods, who did not make the heavens and the earth, will perish from the earth and from under the heavens.’” Jer. 10:11

But God made the earth by his power; he founded the world by his wisdom and stretched out the heavens by his understanding Jer. 10:12

Truth About Christmas Trees

Christmas trees have nothing to do with Christ and have everything to do with pagan worship of false gods. Putting Christ in a pagan ritual does not make it "Christian", it is the ultimate insult to our Lord. Think about this for a minute. If someone robbed you on a certain day each year and then decided that they should have a party and name it after you every year on the same day you get robbed, would you be happy about this? Neither is God. We as a people have been deceived for thousands of years. "The modern Christmas tree originated in Germany. The Germans got it from the Romans, who got it from the Babylonians and the Egyptians.
The following demonstrates what the Babylonians believe about the origin of the Christmas tree: “An old Babylonish fable told of an evergreen tree which sprang out of a dead tree stump. The old stump symbolized the dead Nimrod, the new evergreen tree symbolized that Nimrod had come to life again in Tammuz! Among the Druids the oak was sacred, among the Egyptians it was the palm, and in Rome it was the fir, which was decorated with red berries during the Saturnalia!” (Walsh, Curiosities of Popular Customs, p. 242). 
"The most common justification that one will hear regarding Christmas is that people have replaced old pagan customs and intents by asserting that they are now “focusing on Christ.” I have heard many say that they are “honoring Christ” in their Christmas-keeping. The problem is that God does not say this is acceptable to Him! Actually, He plainly commands against it! Keeping Christmas dishonors Christ! He considers everything about it to be an abomination! We will soon see why. Christ said, “But in vain they do worship Me, teaching for doctrines the commandments of men” (Matt. 15:9). Christmas is not a command of God—it is a tradition of men. Christ continued, “Full well you reject the commandment of God, that you may keep your own tradition” (Mark 7:9). Every year, throughout the world, on December 25th, hundreds of millions do just that" (7)

Biblical Origin of The Christmas Tree

A tree bearing a remarkable resemblence to a Christmas tree is in fact mentioned in the bible. Some groups of people actually worshipped and feared these trees. 

Origin Of Christmas

Contrary to popular opinion Christmas did not originate at the time of Christ's birthday. Read more about the Origin of Christmas here:

• ​Origin of Christmas

Origin of Christmas Decorations and symbols

Believe it or not many of the decorations and symbols used to celebrate Christmas also have pagan origins! Read more about them here:

• Origins of Christmas decorations and symbols

Memory Verse

 “Tell them this: ‘These gods, who did not make the heavens and the earth, will perish from the earth and from under the heavens.’” Jeremiah 10:11

References: 
1. ​Origin of Christmas | The history of Christmas and how it began. (2017). Simpletoremember.com. Retrieved 5 December 2017, from https://www.simpletoremember.com/vitals/Christmas_TheRealStory.htm
​2. HISTORY.com. "History of Christmas Trees - Christmas - HISTORY.com." HISTORY.com. n.d. Web. 5 Dec. 2017. <http://www.history.com/topics/christmas/history-of-christmas-trees>
3. Pack, David C. (December 2015) from http://www.lasttrumpetministries.org/tracts/tract3.html​
4. Christmas tree. (2017). En.wikipedia.org. Retrieved 5 December 2017, from https://en.wikipedia.org/wiki/Christmas_tree
5. ​All about the Christmas tree: Pagan origins, Christian adaptation and secular status. (2017). Religioustolerance.org. Retrieved 5 December 2017, from http://www.religioustolerance.org/xmas_tree.htm
6. ​The history of the Christmas tree. (2016). ABC News. Retrieved 5 December 2017, from http://www.abc.net.au/news/2016-12-19/the-history-of-the-christmas-tree/8106078
7. ​The True Origin of Christmas. (2017). Rcg.org. Retrieved 5 December 2017, from https://rcg.org/realtruth/articles/169-ttooc.html
8. ​Christmas Tree photo by Greyson Joralemon (@greysonjoralemon) on Unsplash. (2018). Unsplash.com. Retrieved 27 September 2018, from https://unsplash.com/photos/huyKOH2v4xE