Christianity is based on the Bible. What does the Bible say about holy days and customs? God warned his people not to learn the way other nations worshiped their pagan gods: "Thou shalt not do to the Lord thy God; for every abomination that the Lord hates, they have done to their gods "(Deuteronomy 12:31).
This reference that bears some resemblance to the modern Christmas tree, in Jeremiah 10: 2-5: "Thus saith the Lord: Learn not the way of the nations, nor the signs of the heavens be afraid, though the nations fear them. For the customs of the people are vanity; because they cut wood from the forest, the work of artificers' hands with a burin. They adorn it with silver and gold; with nails and hammer they affirm it so that it does not move.
This reference that bears some resemblance to the modern Christmas tree, in Jeremiah 10: 2-5: "Thus saith the Lord: Learn not the way of the nations, nor the signs of the heavens be afraid, though the nations fear them. For the customs of the people are vanity; because they cut wood from the forest, the work of artificers' hands with a burin. They adorn it with silver and gold; with nails and hammer they affirm it so that it does not move.