Genesis 16:6

But Abram said unto Sarai
In a meek, mild and gentle manner:

behold, thy maid [is] in thine hand;
though Hagar was Abram's secondary wife he still considers her as Sarai's maid, and as subject to her, and allows her to exercise authority over her; for he still retained the same love and affection for Sarai, his first and lawful wife, and showed the same respect he ever did, and supported her in her honour and dignity:

do to her as it pleaseth thee:
not giving her liberty to take away her life, nor even to use her cruelly, but to deal with her as a mistress might lawfully do with a servant, or however exercise that power which a first wife had over a second: perhaps Abram, in complaisance to Sarai, gave her too large a commission, and left it too much in her power to distress Hagar; and it might have been more correct to have heard both sides, and judged between them, and used his own authority, by reproving and correcting as he saw meet; had she been only Sarai's maid and not his wife, it would have been less exceptionable; however, for peace sake, he gave leave to Sarai to do as she would:

and when Sarai dealt hardly with her;
or afflicted her ^F13, not only with words but with blows, as some think, and unmercifully beat her, and laid hard service upon her she was not able to go through, especially in her circumstances; though it may be she only chastised her in such a manner as a mistress may chastise her maid, since the angel seems to approve of what she did, ( Genesis 16:9 ) ; which her proud spirit not being able to bear,

she fled from her face;
which was set against her, and was full of wrath and fury: she deserted her service, quitted Abram's house though with child by him; unmindful of the various relations she stood in, which should have obliged her to have kept her place, and especially until she had made proper remonstrances of her ill usage, and could have no redress; but, unable to bear the treatment she met with, meditated a flight into her own country, Egypt, for by what follows it appears she steered her course that way; this flight of hers was agreeable to her name, for Hagar in the Arabic language signifies to "flee", hence the flight of Mahomet is called the Hegira.