And when she could no longer hide him
Because of her neighbours, who might hear the crying of the child, or because of the diligent search made by Pharaoh's officers, which some think was made every three months: the Jews F1 have a notion that his mother was delivered of him at six months' end, and therefore when the other three months were up women usually go with child, she could hide him no longer, a birth of a child being then expected, and would be inquired about:
she took for him an ark of bulrushes;
the word, according to Kimchi {b}, signifies a kind of wood exceeding light, so Gersom and Ben Melech; an Arabic writer F3 calls it an ark of wood; it is generally taken to be the "papyrus" or reed of Egypt, which grew upon the banks of the Nile, and of which, many writers say, small vessels or little ships were made, (See Gill on Isaiah 18:2)
and daubed it with slime and with pitch;
with pitch without and slime within, as Jarchi observes; which being of a glutinous nature, made the rushes or reeds stick close together, and so kept out the water:
and put the child therein;
committing it to the care and providence of God, hoping and believing that by some means or another it would be preserved; for this, no doubt, was done in faith, as was the hiding him three months, to which the apostle ascribes that, ( Hebrews 11:23 )
and she laid it in the flags by the river's brink;
among the sedge, weeds, and rushes, that grew upon the banks of the river Nile; there she laid it, that it might not be carried away with the stream of the river, and that it might be seen and taken up by somebody that would have compassion on it, and take care of it: the Arabic writers F4 say, that Jochebed made an ark of the papyrus, though in the law it is said to be of cork, and pitched within and without, and put the child into it, and laid it on the bank of the Nile, where the water was not so deep, by the city Tzan (or Zoan, that is, Tanis), which was the metropolis of the Tanitic nome; but very wrongly adds, that it might be killed by the dashing of the waves, and she might not see its death.