Arcana Coelestia # 3386
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.
Arcana Coelestia # 2507
2507. Of Sarah his wife. That this signifies spiritual truth conjoined with the celestial, is evident from the signification of “Sarah” as a wife, as being intellectual truth conjoined with the Divine good, or what is the same, spiritual truth conjoined with the celestial (see n. 1468, 1901, 2063, 2065, 2172, 2173, 2198). What the spiritual is, and what the celestial, has often been stated before (see n. 1155, 1577, 1824, 2048, 2088). That is called Celestial, which is of good, that is, which is of love to the Lord and of charity toward the neighbor; and that Spiritual, which is of truth, that is, which is of faith derived from those loves.