The "midst" of something in the Bible represents the thing that is most central and most important to the spiritual state being described, the motivation that drives everything else. In general this will be something we love or feel, because at the core of things we are what we love; our loves define us.

(References: Apocalypse Revealed 44, 90, 268; Arcana Coelestia 2252, 2940, 10153, 10365, 10557, 10635, 10641)

2252. That 'perhaps there may be fifty righteous persons in the midst of the city' means that the truths may be full of goods is clear from the meaning of 'fifty' as full, from the meaning of 'righteous' as good, dealt with in 612, 2235, from [the meaning] of 'midst' as that which is within, 1074, and from [the meaning] of 'the city' as truth, 402. Thus 'fifty righteous persons in the midst of the city' in the internal sense means that the truths may be full of goods. That this meaning exists within these words cannot be seen by anyone from the letter, for the historical details of the literal sense lead the mind in an altogether different direction or to think in a different way; but that these words are nevertheless perceived according to that meaning by those who possess the internal sense, I know for certain. Moreover the actual numbers mentioned, such as fifty here, and forty-five, forty, thirty, twenty, and ten in what follows, are never perceived as numbers by those who possess the internal sense but as real things or as states, as shown in 482, 487, 575, 647, 648, 755, 813, 1963, 1988, 2075.

[2] Indeed the ancients also used numbers to mark off one from another the states of their Church; and the nature of such numbers worked out by them becomes clear from the meaning of the numbers in the paragraphs that have just been mentioned. The meaning possessed by numbers was received by those people from the representatives which manifest themselves in the world of spirits. There when anything appears as that which is numbered, it does not mean something defined by means of numbers but means some real thing or else a state, as becomes clear from what has been presented in 2129, 2130, and also in 2089, regarding 'twelve' meaning all things of faith. It is similar with the numbers that now follow. This shows what the nature of the Word is in the internal sense.

[3] The reason 'fifty' means that which is full is that it is the number which comes after seven times seven, or forty-nine, and so marks the completion of the latter number. This explains why in the representative Church the feast of the seven sabbaths ¹ was held on the fiftieth day, and why a jubilee was held in the fiftieth year. Regarding the feast of the seven sabbaths the following is said in Moses,

You shall count for yourselves from the day after the sabbath; from the day you bring the sheaf of the wave-offering, seven sabbaths shall there be complete. Until the day after the seventh sabbath you shall count fifty days, and offer a new gift to Jehovah. Leviticus 23:15-16.

Regarding the jubilee in the same book,

You shall count for yourself seven sabbaths of years, seven times seven years, and you shall have a time of seven sabbaths of years, forty-nine years. And you shall sanctify the fiftieth year and proclaim liberty in the land to all its inhabitants; it shall be a jubilee for you. Leviticus 25:8, 10.

From this it is evident that 'the fiftieth' means that which marks the full completion of the sabbaths.

[4] What is more, whenever 'fifty' is mentioned in the Word it means that which is full, as in the case of the numbering of the Levites aged thirty years and over up to fifty years of age, Numbers 4:23, 35, 39, 43, 47; 8:25. Here 'fifty' stands for the full or final state of that period of ministerial service. A man found lying with a young woman who was a virgin had to give to the young woman's father fifty pieces of silver, and she had to be his wife; nor could he divorce her, Deuteronomy 22:29. Here 'fifty pieces of silver' stands for a full fine and a full recompense. David's giving to Araunah fifty pieces of silver for the threshing-floor, where he built an altar to Jehovah, 2 Samuel 24:24, stands for a full price and a full payment. Absalom's making ready for himself a chariot and horses, and his having fifty men running before him, 2 Samuel 15:1, and Adonijah's likewise having chariots and horsemen, and fifty men running before him, 1 Kings 1:5, stand for their full dignity and majesty. For these people received from the ancients certain numbers which were representative and carried spiritual meanings and which were observed by them. Those numbers were also commanded in their religious observances, though the majority of the people did not know what was meant by them.

[5] In the same way, because 'fifty' means that which is full and this number was also representative, as has been stated, the same thing is meant in the Lord's parable concerning the steward, who said to the man owing oil,

How much do you owe my master? He said, A hundred baths of oil. Then he said to him, Take your bill, and sit down quickly and write fifty. Luke 16:5-6.

'Fifty' stands for the full discharge of the debt. Being a number it does indeed seem to imply nothing more than a number, when in fact in the internal sense this number is used in every case to mean that which is full, as also in Haggai,

One came to the winevat to draw fifty measures from the winevat, and there were only twenty. Haggai 2:16.

This means that instead of a full amount there was not much. 'Fifty' would not have been mentioned in the prophet if it had not carried this meaning.

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