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.

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

2269. 'And He said, I will not destroy it if I find forty-five there' means that mankind would not perish if [goods and truths] could be joined together. This is clear from the meaning of the number 'forty-five' as a joining together. It has been shown already that simple numbers retain their own meaning even when they are multiplied; and so larger numbers have a similar meaning to smaller. So it is with 'forty-five', a number which is the product of five times nine; and because it is the product of five times nine it has the same meaning as five and nine. 'Five' means that which is small, as has been shown already in 649, and 'nine' means conjunction or that which is joined together, 2075; so that the meaning here is, If goods have in some measure been joined to truths. That numbers in the Word mean real things or else states is clear from what has been stated above in 2252 about 'fifty', and also from what has been shown already concerning numbers, in 482, 487, 575, 647, 648, 755, 813, 1963, 1988.

[2] It is because 'five' means that which is small, and 'forty-five' a joining together, that those numbers are used in the way they are in this verse. That is to say, first it is said, 'Perhaps the fifty righteous persons will lack five', which means, If it were something less. Then it is said, 'Will You for five destroy the whole city?' which means, Will they perish for the small amount that is lacking? But after that, because five means a small amount, the number five is not used again but it is said, 'I will not destroy it if I find forty-five there', which means that they would not perish if [goods and truths] could be joined together. And a further reason why the expression 'forty-five' is used, and not 'if the fifty are lacking five', is that 'five' not only means that which is small, as shown in 649, but also severance, as has also been shown in Volume One, in 1686. Consequently so that a joining together might be meant and not a severance, this number, that is to say, forty-five is used, for forty-five means some joining together, as stated above. Thus in a very beautiful way every detail follows in its particular sequence in the internal sense.

[3] As regards good and truth when joined together, this is an arcanum that cannot be described in such a way that the ordinary mind is able to grasp it. Let merely a brief explanation be given here. The more genuine and pure truth is, the better is good from the Lord able to be accommodated to it as the recipient vessel; but the less genuine and pure truth is, the less is good from the Lord able to be accommodated. For they must each answer to the other; and to the extent that they do, they are joined together. Goods cannot possibly be received into falsities, nor evils into truths as their recipient vessels, for they are by nature and disposition contrary. The one rejects the other as its very enemy; indeed if they tried to join together, each of them would throw up - good would throw up evil as though it were poison, and evil would throw up good as though it were something that induces vomiting. Such enmity between evil and good has been provided by the Lord to prevent the possibility of their being mixed together, for if they were so mixed a person would perish. Those who are deceivers and hypocrites come near to having the two joined together in them; yet even in their case the Lord takes care to prevent them becoming joined together. This is the reason why in the next life deceivers and hypocrites suffer more dreadfully than all others.