3386. And he said, She is my sister. That this signifies rational truth, is evident from the signification of “sister,” as being rational truth (n. 1495, 2508, 2524, 2556). By rational truth is meant that which appears as true according to the apprehension, or before the rational, as just said. The arcanum that Isaac said that Rebekah was his sister; as Abraham had before said that Sarah was his sister, first in Egypt (Genesis 12:11-13, 19), and afterwards in Gerar (Genesis 20:2, 5, 12), involves what is much the same, as may be seen from the explication of the former passages; and as the same thing occurred three times, and is three times related in the Word, it is evident that there is in it an arcanum of the greatest moment, which can never be known to anyone except from the internal sense; but what the arcanum is, appears from what follows.

2524. And she herself also said, He is my brother. That this signifies that the rational itself dictated that celestial good should be adjoined to it, is evident from the signification of a “sister” (here meant by “she herself”) as being the rational (n. 1495, 2508); and from the signification of a “brother,” as being the good of truth (n. 367, 2508). For the case herein is as follows: Divine good and Divine truth are united to each other as if by marriage; for thence comes the heavenly marriage, and thence comes marriage love also, even down to lower nature. But the good and truth of the rational are not conjoined with each other as by marriage, but by consanguinity, like brother and sister; since the rational as to truth is conceived from the influx of Divine good into the affection of knowledges [scientiarum et cognitionum] (see n. 1895, 1902, 1910); and the good of the rational, through the influx of Divine good into that truth, which then becomes the good itself of charity, which is the “brother” of faith, or what is the same, of truth (n. 367)

[2] But in regard to the good and truth of the rational, the procuring of this takes place in such a way that its good is from Divine good, whereas its truth is not from Divine truth; for the truth of the rational is procured by means of knowledges [scientias et cognitiones], which are insinuated through the external and internal senses, thus by an external way. Hence it is that there adhere to its truths many fallacies from the senses, which cause the truths not to be truths; nevertheless when Divine good flows into them, and conceives them, they then appear as truths, and are acknowledged as truths, although they are nothing but appearances of truth. The good itself is then modified in these truths according to the shades there, and becomes in quality like the truth. This is one arcanum which lies hidden in these words, that the rational thus dictated that celestial good should be adjoined to it.