Most of the time, falling means a lowering in spiritual state, from one closer to the Lord to one further. But, as with other common verbs, the meaning of "fall" is highly dependent on context in regular language, and in the spiritual sense as well. People fall on their faces in prayer, fall in battle, fall on others to attack them and fall on each other's necks in greeting. Stars fall from the sky, mountains fall on people, cities fall, and even faces fall. There's a lot of falling, in very different circumstances. When people fall on their faces in prayer -- it shows humility, and an acknowledgement of their own low state and need for the Lord's help. When they fall on each other's necks, it means a communication between the two spiritual states. At the other end of the scale, it illustrates complete spiritual destruction in the fall of a city.

1020. And the cities of the nations fell, signifies that all things of the doctrine of good from the Word were likewise dissipated. This is evident from the signification of a "city," as being doctrine (as just above); so "cities" mean doctrinals, or all things of doctrine. Also from the signification of "nations," as being those who are in the good of love, and in an abstract sense goods (See n. 175, 331, 625). Also from the signification of "falling," as meaning to be dissipated, for when cities fall they perish, and when doctrine falls its truths are dissipated.

(Continuation respecting the Eighth Commandment)

[2] When a man abstains from false testimonies understood in a moral and spiritual sense, and shuns and turns away from them as sins, the love of truth and the love of justice flow in from the Lord through heaven. And when, in consequence the man loves truth and loves justice he loves the Lord, for the Lord is truth itself and justice itself. And when a man loves truth and justice it may be said that truth and justice love him, because the Lord loves him; and as a consequence his utterances become utterances of truth, and his works become works of justice.