Did the first Christian believers keep the Sabbath and if so on which day?

According to Colossians, there appears to be some disagreement amongst the first century church on *whether* to keep the Sabbath: > Colossians 2:16 > > Therefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a **Sabbath day**. Did the first century church keep the Sabbath? And if so which day was it on? The Jewish Saturday or the new Christian Sunday?