So, for most of the New Testament, that word "apostle" and "disciple" are kind of interchangeable terms. The twelve disciples become the twelve apostles with a little bit of change. When it comes to the apostles' teaching, we're talking specifically about men who were close followers of Jesus before His death and who saw him after His resurrection. The bigger question for us today is: What are the things that the first leaders of the church taught? Because they had sat with Jesus, they had lived with Jesus, they had devoted their lives to Jesus. What were the top things that they focused on when teaching the first generation of the church? What were those biggest, most important things that they were going to teach?