Buy a sword (agorasatw macairan). This is for defence clearly. The reference is to the special mission in Galilee ( Luke 9:1-6 ; Mark 6:6-13 ; Matthew 9:35-11:1 ). They are to expect persecution and bitter hostility ( John 15:18-21 ). Jesus does not mean that his disciples are to repel force by force, but that they are to be ready to defend his cause against attack. Changed conditions bring changed needs. This language can be misunderstood as it was then.