The names of the Twelve (Mark 3:13; Luke 6:12; Acts 1:13). At an early period in His Galilean ministry, Jesus selected Twelve from among the disciples already called (Mk, Lk), after spending a night in prayer in 'the mountain' (Lk), as befitted so solemn and important an act. The 'Sermon on the Mount' constituted their ordination address (Lk). St. Matthew assumes these facts to be known, and introduces the Twelve abruptly, Now the names of the twelve apostles are these, without mentioning how they were called together. The chief significance of the appointment of the Twelve is that it indicates the design of Jesus to provide His society with an ordained ministry, and to give it a thoroughly efficient organisation to cope with its world-wide mission. The number twelve was suggested by the number of the Jewish patriarchs. The apostles were to be the patriarchs or spiritual ancestors of the new Israel.
The names of the apostles are always given in three groups of four names, of which the leaders (Peter, Philip, James of Alphseus) are mentioned first in all the lists. The names are always kept in their own groups, but vary in order, except that the leader is always placed first.