What does Genesis 16:7 mean?

Over the last few verses, Abram and Sarai's plan to speed up God's timetable has gone terribly wrong. Sarai's idea was to follow the customs of her time. She would give her Egyptian servant girl Hagar to Abram as his wife. When Hagar bore a child, the child would, belong to Sarai. This, in her mind, would solve the problem of her own barrenness.

Of course, this alternate route to God's promise backfired. Once pregnant and married to Abram, Hagar became contemptuous of Sarai. In the context of that culture, this is hardly a surprise. After all, she had accomplished, seemingly immediately, what Sarai never could. Sarai had to force Abram to confirm that she was still in authority over Hagar. Once he agreed, she "dealt with" Hagar very harshly. And so, Hagar ran, maybe for her life.

Now pregnant and alone, Hagar escapes into the wilderness, to a spring on the road to Shur. Hagar may have been heading back to her homeland of Egypt. The "angel of the Lord" found her by that spring. This "angel of Yahweh" may have been a theophany: God taking on a human form on earth to accomplish a specific purpose. Alternatively, this might have been some other angel or angelic being. The context and phrasing of this chapter seem to suggest this was, in fact, the Lord Himself (Genesis 16:10, 13).