What to study... The Apostles' Teaching

And they devoted themselves to the apostles' teaching and the fellowship, to the breaking of bread and the prayers. (Acts 2:42 ESV)
When these first believers came to realize Who Christ was, What He had done, and what they had done, they needed to know all about Him. So they learned from those who knew - the Apostles. Not only did the apostles know what Jesus had said and done, they also had an extended debrief session with Jesus before His ascension back to heaven, when he told them how it all fit with the Old Testament. The Gospel He entrusted to the Apostles had much teaching, which we now find in the New Testament. It's what we need to know, to study. Let's dig in.