What do you think the biggest misunderstanding about Christmas is?
That what is celebrated today has any remote connection to the birth of Jesus Christ in the first place.
Reading through the gospel accounts of the birth of Jesus (Matthew ch 2; Luke ch 2) we find details from both accounts that fill in different detail but Luke sets the time period, when
Publius Sulpicius Quirinius was governor of Syria.
Quirinius - Wikipedia
Every male had to return to the place of their birth to register for a census. Mary and Joseph were in Nazareth and had to travel to Bethlehem even though Mary was close to full term for her pregnancy. Because of the all the people who had come into the town, accommodations were full. There was no room in the lodging place for Joseph and Mary to stay, so the innkeeper apparently recognizing their circumstances, allowed them to stay in a place where animals fed since, the baby was "laid in a manger" or a feeding trough for animals. This also fulfilled a prophesy in Isaiah 53:2 concerning the humble circumstances of Jesus' life and his birth.
(Luke 13:15 uses the same word......
"But the Lord answered him and said, “You hypocrites, does not each of you on the Sabbath untie his ox or his donkey from the stall G5336 and lead him away to water him? Strongs)
It was Jewish shepherds who were informed about the birth of the Messiah by angels, and it was these who journeyed to Bethlehem to see the new born King. There is no mention of the "wise men" being there. If they had been, then the gifts they gave Mary and Joseph would have allowed them to offer the prescribed sacrifice at the temple, but all they offered were two turtledoves, the offering of the poor.
The so-called "wise men" were Babylonian astrologers who arrived much later and were not directed to Bethlehem and to the "house" where Jesus was then living with his parents, but to Jerusalem and to a jealous king who, when he was informed that a new king had been born, determined that no other king would succeed him but his own sons. He hatched a plot to locate the child with the intention to do away with him. It failed of course because it was not God who sent the star, but the devil, using his own dupes to try and get rid of the Messiah before he even had a chance to grow up. The star then becomes the means that satan used to lead Herod to Jesus, knowing his cruel disposition. The mass slaughter of infants under the age of two, resulted.
The date of Jesus' birth is not recorded in scripture for a good reason. Jews did not celebrate birthdays and it was forbidden to Jews to adopt the customs of the Gentile nations. Birthdates were used in astrology for casting horoscopes and the celebration of birthdays was filled with spiritistic customs which are still carried on today. The birthday wishes were for the spirits to be kind to the newborn....the cake with the candles was to ward off evil spirits......none of these are acceptable to God because of their origins. (Deuteronomy 18:9-12)
The northern hemisphere winter customs associated with Christmas are all pagan...the decorated tree...the Yule log....the feasting and merry-making....gift giving....carols....Santa Claus.....none of them have anything to do with Jesus and are all in fact offensive to God and his Christ. Far from honoring them, these pagan adoptions, dishonor them. Knowing all of that...how could they not?
So to me, the biggest misunderstanding is that Christ was ever IN Christmas.