Christmas, cutting trees and decorating it, etc., are a man's tradition (heathen)
God does not approve of it

Jer 10:1-11, CHAPTER 10

1. Hear ye the word which the LORD speaketh unto you, O
house of Israel:
2. Thus saith the LORD, Learn not the way of the heathen,
and be not dismayed at the signs of heaven; for the heathen are
dismayed at them.
3. For the customs of the people are vain: for one cutteth a
tree out of the forest, the work of the hands of the workman, with
the axe.
4. They deck it with silver and with gold; they fasten it with
nails and with hammers, that it move not.
5. They are upright as the palm tree, but speak not: they
must needs be borne, because they cannot go. Be not afraid of
them; for they cannot do evil, neither also is it in them to do
6. Forasmuch as there is none like unto thee, O LORD; thou
art great, and thy name is great in might.
7. Who would not fear thee, O King of nations? for to thee
doth it appertain: forasmuch as among all the wise men of the
nations, and in all their kingdoms, there is none like unto thee.
8But they are altogether brutish and foolish: the stock is
a doctrine of vanities.
9Silver spread into plates is brought from Tarshish, and
gold from Uphaz, the work of the workman, and of the hands of the founder: blue and purple is their clothing: they are all the
work of cunning men.
10. But the LORD is the true God, he is the living God, and
an everlasting king: at his wrath the earth shall tremble, and the
nations shall not be able to abide his indignation.
11. Thus shall ye say unto them, The gods that have not
made the heavens and the earth, even they shall perish from
the earth, and from under these heavens.