491. The same things are signified by “sons” and “daughters” in this chapter (verses 4, 7, 10, 13, 16, 19, 26, 30), but such as is the church, such are the “sons and daughters” that is, such are the goods and truths; the truths and goods here spoken of are such as were distinctly perceived, because they are predicated of the Most Ancient Church, the principal and parent of all the other and succeeding churches.
Arcana Coelestia # 1960
1960. That 'Hagar bore Abram a son' means the rational man born from that coming together and conception is clear from the representation and meaning of 'Hagar', 'Abram', and 'son'. 'Hagar' means the life which is present in the affection for knowledge and which belongs to the exterior man, as stated above in 1895, 1896; 'Abram' means the Lord's Internal Man, 1893, 1950; and 'a son' means truth, and so the truth which this rational possessed, 264, 489, 491, 533, 1147. Consequently the words 'Hagar bore for Abram' mean the rational man born from that conception and coming together. This is the sense into which the sense of the letter is converted when it comes to or resides with angels.