In the ancient and Jewish churches, 'songs' were prophesies about the Lord, especially His coming in the world, subjugation of evil spirits, and liberation of the faithful from their assaults. 'Heavenly songs' are voiced affections or affections expressed and modified by sounds. As thoughts are expressed by conversation, so affections are expressed by songs. From the balance and flow of the variations, angels perceive the object of the affection.

(Reference: Conjugial Love 55)

3924. Verses 7-8 And Bilhah, Rachel's servant-girl, conceived again and born a second son to Jacob. And Rachel said, With the wrestlings of God I have wrestled with my sister, and I have prevailed. And she called his name Naphtali.

'Bilhah, Rachel's servant-girl, conceived again and bore' means here, as previously, reception and acknowledgement. 'A second son to Jacob' means a second general truth. 'And Rachel said, With the wrestlings of God I have wrestled with my sister, and I have prevailed' in the highest sense means [the Lord's] own power, in the internal sense temptation in which a person overcomes, in the external sense resistance offered by the natural man. 'And she called his name Naphtali' means the essential nature of it.