Arcana Coelestia # 3137
3137. 'At the spring' means the enlightenment of them from Divine truth. This is clear from the meaning of 'a spring' as truth, dealt with in 2702, 3096, here Divine truth, as above in 3131. Because the Word is Divine truth it is therefore called 'a spring'. That 'standing at the spring' here embodies in the internal sense the enlightenment of things in the natural man follows from the train of thought; for where Divine truth is, enlightenment is there.
Comfort
When the Bible talks about someone being comforted or consoled, it generally means that they are being offered ideas that will help bring them to a more peaceful spiritual state, whether it is a new state or the restoration of one that had been under attack. It's interesting; we tend to think of comforting someone as an emotional thing, offering our own feelings to help them feel better. But the Writings say that the spiritual meaning of 'comfort' is actually more intellectual, coming when a person gains new true ideas.
In Genesis 5:29, this signifies doctrine whereby what was perverted may be restored. (Arcana Coelestia 531)
In Genesis 27:42, this signifies intent to invert the current spiritual state.