Keluaran 7:23-24

7:23 And Pharaoh turned and went into his house. He did not pay any attention to this. ¹  7:24 All the Egyptians dug around the Nile for water to drink, ²  because they could not drink the water of the Nile.

[7:23]  ¹ tn The text has וְלֹא־שָׁת לִבּוֹ גַּם־לָזֹאת (vÿlo’-shat libbo gam-lazo’t), which literally says, “and he did not set his heart also to this.” To “set the heart” to something would mean “to consider it.” This Hebrew idiom means that he did not pay attention to it, or take it to heart (cf. 2 Sam 13:20; Ps 48:13; 62:10; Prov 22:17; 24:32). Since Pharaoh had not been affected by this, he did not consider it or its implications further.

[7:24]  ² sn The text stresses that the water in the Nile, and Nile water that had been diverted or collected for use, was polluted and undrinkable. Water underground also was from the Nile, but it had not been contaminated, certainly not with dead fish, and so would be drinkable.