4725. 'And they said, a man to his brother' means the thoughts held mutually by them. This is clear from the meaning of 'saying' as perceiving and thinking, dealt with in 3395; and from the meaning of 'a man to his brother' as mutually. Among the ancients 'a man to his brother' was a customary saying used by them to mean something mutual, the reason being that 'a man' meant truth, 3134, 3459, and 'a brother' good, 4121, and a perfect mutual bond exists between truth and good. For when truth is joined to good, and good to truth, the action is mutual and reciprocal, 2731.

3889. To enable me to know not only that there is a correspondence of celestial things, which are those of love, with the motions of the heart, and of spiritual things, which are those of faith derived from love, with the motions of the lungs, but also the nature of this correspondence, I was allowed to spend a significant amount of time with angels who were to demonstrate this to me visually. By means of wonderful circular movements, impossible to describe, they formed a resemblance of the heart and a resemblance of the lungs, including all the intricate interior and exterior parts which the heart and lungs possess. They traced the spontaneous flow of heaven, for heaven strives to exhibit that form from the influx into itself of love from the Lord. In this manner each individual part of the heart was exhibited, and after that the union of the heart and the lungs, which union they also represented by means of the marriage of good and truth. From this also it was evident that the heart corresponds to the celestial element of good and the lungs to the spiritual element of truth, and that the material form in which the two exist joined together is the heart and lungs. I was also told that the same applies throughout the whole body, that is, to things of the heart and those of the lungs within all the individual members, organs, and viscera of the body. For where the two are not acting together but each one by turns separately, no motion of life belonging in any way in the will can exist there nor any feeling of life beginning in any way in the understanding there.