Jesus' final words make it clear that circumstances are changing. Opposition to the disciples is rising. Where before Jesus had sent them out empty-handed yet they were provided for (9:1-6; 10:3-4), now they will have to take provisions and protection for their travel. They will have to procure a sword. Scripture such as Isaiah 53:12 is finding its fulfillment in Jesus. Jesus is rejected; he is numbered with the transgressors.
The disciples take Jesus' remarks literally and incorrectly. They note that they have two swords, but Jesus cuts off the discussion. Something is not right, but it is too late to discuss it. As the arrest will show, they have misunderstood. They draw swords then, but Jesus stops their defense in its tracks. He is not telling them to buy swords to wield in physical battle. They will have to provide for themselves and fend for themselves, but not through the shedding of blood. They are being drawn into a great cosmic struggle, and they must fight with spiritual swords and resources. The purchase of swords serves only to picture this coming battle. This fight requires special weapons (Eph 6:10-18).
I don't know where you got these statements but if the swords were not "literal", why then in Luke 22:38, when they said, "Lord, behold, here are two swords." (they showed him literal swords) He said, "It is enough". I believe your point of view is wrong. The swords are literal, so you need not write or quote a lot of stuff that is not in the Bible, but only of your transliteration.
Two different situations.
Christ was remaining obedient to legitimate authority, namely the authority of God the Father. He had legions of angels at His disposal to dispatch, but His direction was to obey the authority of God the Father. In the Garden of Gethsemanie, He was preparing for the soon to be administered judgment.
The later direction to sell one's cloak to buy a sword for self defense was for those spreading the ospel in areas known for criminal elements in their midst.