Genesis 21:19

Abraham took it very hard when Hagar fled from him, though he had sent her off at God's command. Similarly it was a great cause of sorrow to the holy apostles and evangelists when Israel fell. However, they were separated from them, not at all willingly but because of God's will and out of love for Christ. For this reason the divine Paul writes, "My sorrow is great, and I have continuous pain in my heart, for I would wish that I myself could be separated from Christ for the sake of my brothers, who are from the same race as I according to the flesh; they are Israelites." So, when the mother of the Jews was sent away, she wandered for a long time in the wilderness, and there was some danger of her being wholly destroyed. But if she should begin to weep (like Hagar) in time and cry out to God, she will be shown mercy abundantly. For God will open the eyes of their understanding, and they too will see the fountain of living water, that is, Christ. And believing they too will rejoice, and having been washed they will be made clean, according to the saying of the prophet.

"He opened her eyes," the text goes on, not because she couldn't see before this but because even with her eyes open nothing was of any help to her before the visitation from on high. Hence, since his intention was to give evidence of care on his part, it says, "He opened her eyes," that is, he made clear to her in her ignorance, he activated her mind, he showed her the way to find the place flowing with springs of water. "She saw a well of running water," the text goes on, "and she went and filled the bag, and gave the boy to drink." In her neediness the Lord granted her means, and when she found herself so much at a loss and lacking all hope of survival, he gave evidence in her case of his characteristic generosity by consoling her and at the same time exercising care for the child.In like manner, whenever God wishes, even if we are utterly alone, even if we are in desperate trouble, even if we have no hope of survival, we need no other assistance, since God's grace is all we require. You see, if we win favor from him, no one will get the better of us, but rather we will prevail against anyone. "God was with the boy," the text goes on; "he grew up and lived in the desert." In similar fashion, whenever we have God on our side, even if we are utterly alone, we will live more securely than those who dwell in the cities. After all, the grace of God is the greatest security and the most impregnable fortification.