He appointed twelve that they might be with him and that he might send them out to preach. Mark 3:14
The order in which Mark, the author of this gospel, describes Jesus calling of His disciples is critically significant. Jesus’ intention was that first they were to “be with” Him, to spend time in His presence, hang out together with Him and get to know Him and His ways. Then and only then, when they had become immersed in His presence and shaped to faithfully represent His name and nature, would He sent them out to preach. Although the task of going forth as His ambassadors was His ultimate purpose Jesus first calling to His disciples was that they might simply be with Him.
It reflects the priority Jesus placed throughout His earthly ministry on being preceding doing and the necessity of doing then flowing out of being. The spiritual journey of every disciple who is seeking to follow Jesus must always follow this pattern.