John Gill Commentary Nehemiah 9:11

"And thou didst divide the sea before them, so that they went through the midst of the sea on the dry land; and their pursuers thou didst cast into the depths, as a stone into the mighty waters." — Nehemiah 9:11 (ASV)

And you did divide the sea before them, so that they went
through the midst of the sea on dry land
That is, the Israelites, see (Exodus 14:21) ,

and their persecutors you threw into the deeps ;
with great ease, and with indignation, meaning the Egyptians, that pursued hotly after them, and were thrown into the sea:

as a stone into the mighty waters ;
where they sunk and perished, see (Exodus 15:4Exodus 15:10) .