Psalms 78:44 - Exposition

And had turned their rivers into blood (see Exodus 7:19 , Exodus 7:20 ). "Their rivers" are the many branches of the Nile, some natural, some artificial (Herod; 2.17), by which Lower Egypt is traversed. And their floods; or, their streams; i.e. the smaller canals, which diffused the Nile water over the entire land. That they could not drink (see Exodus 7:21 ).