With the cross looming into view, Jesus prepared His trainee apostles for the next few days, which would be the pattern for the rest of their ministries.  He reminded them of the times when they went out in His Name (Luke 9:1-6; Luke 10:1-20).  When they operated under His authority, they had all they needed: even when they went away from Jesus on mission trips, the Lord provided for their needs, using His servants along the way.  But shortly, they would be on their own; weak, frightened and apparently defenceless.  
 
The instruction to take a sword or two into Gethsemane was also important for at least three different reasons.  A weapon would give them a strong clue that they were entering a major conflict (although they had no idea about the nature of the battle with Satan, death and hell - they needed to be ready, to watch and pray ... although they were to fail dismally).  They needed to find out that no weapon or well-intentioned human effort could stop God's crucifixion plan for Jesus (and the disciples would feel useless and helpless).

But in addition, the disciples had a significant part in the unfolding drama. The arrest of Jesus in the Garden needed a legal reason, and the swords could be taken as evidence that He was the leader of an armed band of terrorists.  Two swords were quite sufficient to prove that point - reinforced by Peter's clumsy attempt to kill the servant of the High Priest (Matthew 26:51-54).
 
When God makes His plans, they are always fit for their purpose (Jeremiah 29:11).  He knows exactly what is needed.  Sometimes He provides in abundance so that we might praise Him, and wonder at His generosity.  But often He will only supply just enough for each bit of the task or journey.  Why?  He knows our human nature, how much we like to feel in control and how easily we convert His generosity into our personal power-base.  Like the Israelites, going through the wilderness, who only had enough manna to eat for each day (Exodus 16:14-30), the Lord will train us in discipleship by showing us the inadequacy of our own store of resources and the sufficiency of His.  So do not fret when the Lord's 'enough' does not seem big enough.  His care is greater than we think; His timing is better than we know.  His ability to use one set of circumstances to achieve multiple objectives is breath-taking (in retrospect), although we cannot work it out at the time.  The Lord's 'enough' is often our greatest training in faith.  So do not resist His kind withholding of all that you want when He is training you for the privilege of royal service.