In Genesis 21:16, being a bowshot away signifies the state and degree of absence from the doctrine of truth. (Arcana Coelestia 2685)

2685. 'Withdrawing herself about a bowshot' means the extent to which the state was away from the doctrine of truth. This is clear from the meaning of 'being withdrawn from' as being away from, and from the meaning of 'a bow' as the doctrine of truth, dealt with in the next paragraph. 'Shot' means that it was as far away as possible, as far away as an arrow could be shot from a bow. Here the expression 'a bowshot' is used because the bow is used in reference to the spiritual man, who is also called 'an archer', as he is in verse 20 - 'and he dwelt in the wilderness, and was an archer'.