Arcana Coelestia#4001
4001. 'And black among the lambs' means the first state of innocence. This is clear from the meaning of 'black' as the proprium, and from the meaning of 'a lamb' as innocence, dealt with just above in 3994. The reason why 'black among the lambs' at this point means the first state of innocence is that the proprium of a person who is being regenerated rules at first, for he imagines that he does good from his proprium, and also, so that he can be granted a heavenly proprium, he must do it as if from his proprium, see 1712, 1937, 1947, 2882, 2883, 2891. This is why 'black among the lambs' here means the first state of innocence.
Arcana Coelestia#2736
2736. I have been informed that genuine conjugial love is innocence itself, which resides in wisdom. With those who have lived in conjugial love wisdom exists more than with all others in heaven, yet when looked at by others they are seen as little children in the bloom and springtime of life; and whatever happens, it is joy and happiness to them. They are in the inmost heaven, which is called the heaven of innocence. Through that heaven the Lord flows into conjugial love, and angels from it are present with men and women who live in that love. They are present also with little children in the first years of their life.