God opened her eyes— God caused her to see what she had not before observed, through her grief and disorder of mind. Le Clerc observes from Diodorus Siculus, that it was usual with the Arabians to cover up their wells' mouths, and lay them over with sand or earth, leaving only some mark, whereby they themselves might know them.
Related Commentaries of Genesis 21:19
Genesis 21:19
19 And God opened her eyes, and she saw a well of water; and she went, and filled the bottle with water, and gave the lad drink.