这句是对上句的概括，远离金银是城邦护卫者不陷入“rascality”的保全之法。只有作为理想国最高统治者不受外物左右，那么理想国自然而然就得到了救赎。

And this will be their salvation, and the salvation of the State.
这将是他们的救赎，亦是理想国的救赎。

所在段落

The Story of Philosophy《哲学的故事》第1章Plato第7节VI. The Political Solution第5段第5句：

So much for incompetence; as for rascality we may provide against that by establishing among the guardians a system of communism:
In the fist place none of them should have any property beyond what is absolutely necessary; neither should they have a private house, with bars and bolts, closed against any one who has a mind to enter; their provisions should be only such as are required by trained warriors, who are men of temperance and courage; their agreement is to receive from the citizens a fixed rate of pay, enough to meet the expenses of the year, and no more; and they will have common meals and live together, like soldiers in a camp. Gold and silver we will tell them that they have from God; the diviner metal is within them, and they have therefore no need of that earthly dross which passes under the name of gold, and ought not to pollute the divine by earthly admixture, for that commoner metal has been the source of many unholy deeds; but their own is undefiled. And they alone of all the citizens may not touch or hand silver or gold, or be under the same roof with them, or wear them, or drink from them. And this will be their salvation, and the salvation of the State. But should they ever acquire homes or lands or moneys of their own, they will become housekeepers and husbandmen instead of guardians; enemies and tyrants instead of allies of the other citizens; hating and being hated, plotting and being plotted against, they will pass through life in much greater terror of internal than of external enemies; and the hour of ruin, both to themselves and to the rest of the State, will be at hand(416-417).
浙江大学译本： 这将是使他们自已免于灾难的救赎之道，同时也是理想国的救赎之道。

上句见：Day455