Consider this - Job, blameless and upright actually celebrated birthdays with his family.
According to the New World Translation Job 1:4,5 says this -
4 And his sons went and held a banquet at the house of each one on his own day; and they sent and invited their three sisters to eat and drink with them.
5 And it would occur that when the banquet days had gone round the circuit, Job would send and sanctify them; and he got up early in the morning and offered up burnt sacrifices according to the number of all of them; for, said Job, “maybe my sons have sinned and have cursed God in their heart.” That is the way Job would do always.
Some translations render the statement 'each one on his own day' as each one on his birthday. Job's seven sons were grown and each had their own houses. On "his day," they would invite their siblings to a party. "His day" is the same word translated "the day of his birth" in 3:1, and nearly every commentator understands "his day" to mean "his birthday."
The celebration of birthdays does go very far back into human history. However, notice that it is the "birthday boy" who throws the party for others, exactly the opposite of the way we celebrate birthdays today. In Genesis 40:20, 'when it... was Pharaoh’s birthday... he made a feast for all his servants...' In this case, the brother would invite his nine siblings to the party.
However what about verse 5? Did Job then feel that a sin had occured? Didn't he offer up burnt sacrafices and say 'maybe my sons have sinned...' Therefore should we take this to be another example in the bible of birthdays being unscriptual?
Actually no.
Job was not sure if they had sinned! Job did not say, "my sons are celebrating their birthdays which is against the will and law of God, and is sin." If Job knew for sure that birthday celebrations were sin, per se, he would have had no doubt that they all had sinned! But Job was not sure f they had sinned by getting together "each on his day". It is obvious Job did not think that was sin to do, if so he would have had no doubts whatsoever that they had sinned just by that act alone.
Yet, Job did have doubt as to whether they had sinned. The doubt did not arise over "birthday celebrations" at all, if you read the passage it says, "It maybe my sons have sinned and cursed God in their hearts." It was not the practice of celebrating a birthday that God had revealed was a sin to Job and that he was upset about his children practicing. It was their heart's attitude and what they were thinking that Job was concerned about. He was worried they "maybe" the boys had sinned against God in their minds and hearts.
Nothing in these verses says birthday celebrations are a sin. Job was not even sure if in fact they actually had sinned. But he didn't want to take any chances, so he offered sacrifice to cover the chance they had sinned. If God wanted to use the bible to illustrate that celebrating birthdays is unscriptual here was a perfect opportunity. This section of the bible has nothing to do with teaching us that birthday celebrations are wrong and the plain truth can be seen by reading just what is written - adding no more and no less.
So, Job did the offering to God just in case his children did not thank God themselves. This shows that Job loved God. He loved God so much that he would thank God for the blessings of his children just in case they did not thank God themselves.
Therefore my friends here at JWD - go forth and celebrate your birthdays! And have fun!!!