Whether through a cursory read or because we grew up with a certain understanding taught us as a child, we often have preconceptions about Jesus and the Apostles. I’m not certain, as a little boy, if I thought Jesus and the Apostles lived together, but I did believe they went everywhere together. This became a little confusing after I learned that the Apostles had families, because I didn’t understand how family life fit into the lives of the Apostles, if they spent every hour of their lives with Jesus. Certainly the New Testament teaches that, if a man doesn’t provide for his own family, he is worse than someone who rejects Jesus out of hand. So, how would that fit into the idea that the Apostles left everything for Jesus (Luke 5:28, 18:23)? After awhile some things just didn’t fit, so they were simply ignored for want of a logical answer. I came to understand that not every detail can be known, but the problem is: what we do have are pretty significant details.
It is implied in the text at Luke 9:1 that the Twelve were not together in one place before Jesus brought them together. How might we understand this? In each of the four lists of apostles (Luke 6:13-16; cf. Acts 1:13; Matthew 10:1-4; Mark 3:13-19) Peter, Philip and James (the son of Alpheus) are always in the same positions, i.e. first, fifth and ninth. All the other names of apostles may vary in position after each of the three fixed names, but even they don’t vary so much that they follow other fixed names. In other words, Andrew, James and John always follow Peter and never Philip or James (son of Alpheus). Likewise, Thomas, Matthew and Bartholomew always follow Philip; and Jude, Simon (the Zealot) and Judas Iscariot always follow James (son of Alpheus).
When the lists are compared there appears to be three groups of four apostles each. This may mean that Jesus had specific duties for each group. For example, Judas held the bag (John 12:6). That is, he seems to have been the treasurer of the group, and his sub-group may have been particularly responsible for financial liabilities and for charitable contributions etc. Philip and his sub-group may have been responsible for record keeping (Matthew was a tax-collector and previously kept records) and how the group’s finances would be spent (cf. John 6:5-7). Finally, Peter’s group may have been responsible for organizational duties. This sub-group may have planned the groups trips, where they would stay etc. (cf. Luke 22:8) and may have had certain duties pertaining to making appointments for Jesus (cf. John 12:20-22).
If all of the Twelve were not always with Jesus all of the time (cf. Luke 9:1), how might Jesus have split them up on various occasions? First of all, there seems to have been times when Jesus spent one-on-one time with his disciples: see Peter (Matthew 8:14; 17:24-26), Matthew / Levi (Luke 5:29) and Simon, the Zealot / Pharisee (Luke 7:36-50). There were times when he had only Peter, James and John with him (cf. Luke 8:51; 9:28). There may have been occasions when he spent time with a single sub-group. For example, if he spent time with Simon, the Zealot / Pharisee (Luke 7:36-50), Jesus may have spent time only with those whose homes were in Judea. Simon’s house was in Bethany, and Judas Iscariot, Simon’s son (John 6:71; 12:4) may have been with him. Moreover, James, the son of Alpheus, and his son, Jude (Thaddeus) may have lived in or near Jerusalem where his mother, Mary, and father lived (Matthew 27:56; Mark 14:40). Jesus could also have spent time with only two from each sub-group, while the others spent time with their families.
Jesus may have often spent time with a smaller number of apostles for a number of reasons. It is possible that he desired to engage in special training for particular members, or simply teach a smaller number of the Twelve on one occasion and their counterpart on another occasion. He would have been sensitive to the needs of family and didn’t want his disciples to spend long extended periods away from their loved ones. Therefore, smaller groups were trained and taught on different occasions.
During certain periods, it would have been necessary for the whole number of the Twelve to be together. For example, on major trips to Jerusalem around the Holy Days, whole families might be expected to make a pilgrimage together. On these occasions the whole group would be together. There were times when Jesus wanted the entire group to experience a certain matter together, such as when they went to Caesarea Philippi. The geographic location was important for the point he wished to make about himself. So, it would have been necessary for the whole group to be together. In the matter concerning Luke 9:1-10 Jesus wanted to send out the entire group, two-by-two, to preach the Gospel of the Kingdom around the vicinity of Galilee, so the presence of the Twelve was necessary.