Happy St. Nicholas day! What is St. Nicholas all about? If images of "Santa Claus" came to your mind, then you went in the completely wrong direction. Take everything you know about "Santa Claus" and toss it out. He has almost nothing to do with the real St. Nicholas. In fact, the only Saint I know of whose association is more distorted than St. Nicholas is St. Valentine. The celebration that occurs every year on February 14th in his honor is an awful distortion of what he was all about (the error is based on the fact that he performed marriages when the Roman Empire said it was illegal).
So then, what was St. Nicholas really known for? He was the Bishop of Myra (in modern day Turkey) in the 4th century. There are various legends that surround him and none of them directly relate to Christmas per se. The closest one that people have often heard of is that he put gifts into poor children's socks that were hanging to dry. It does not appear that it was in relation to Christmas, but rather to his commitment to give to the poor. If you are going to honor a Saint, it should be done in truth (not modernist myths that are known to be in error).
What he is more known for, however, is his fight against Arianism. Apparently, while at the council of Nicea in 325, he was said to have punched (or maybe just slapped) Arius himself in the face. He considered the arian heresy to be a horrible evil (it was, after all, an attack on the very person of Christ). As a result he was stripped of his episcopal insignia and sent to prison. Interestingly, the Lord appeared to disagree with that decision. Christ and the Blessed Virgin appeared to him in prison, restored him to his office, and freed him to return to ministry (!).
Is that the St. Nicholas that you are thinking about today? The devil would love it if you forgot who the real Saint was, and focused instead on an errant notion of a "fat, jolly guy who gives you stuff". Look deeper to see who he was (even if some of the stories are just legendary, they reveal the type of character he was known for). At the beginning of Advent, it would be wise for us to keep our focus on the truth, and look to honor our Lord and His Saints for who they really were.