He turned their heart, etc... Not that God (who is never the author of sin) moved the Egyptians to hate and persecute his people; but that the Egyptians took occasion of hating and envying them, from the sight of the benefits which God bestowed upon them.
104:26. He sent Moses his servant: Aaron the man whom he had chosen.
104:27. He gave them power to shew them signs, and his wonders in the land of Cham.
104:28. He sent darkness, and made it obscure: and grieved not his words.
Grieved not his words... That is, he was not wanting to fulfil his words: or he did not grieve Moses and Aaron, the carriers of his words: or he did not grieve his words, that is, his sons, the children of Israel, who enjoyed light whilst the Egyptians were oppressed with darkness.
104:29. He turned their waters into blood, and destroyed their fish.
104:30. Their land brought forth frogs, in the inner chambers of their kings.
104:31. He spoke, and there came divers sorts of flies and sciniphs in all their coasts.
Sciniphs... See the annotation, Ex.8.16.
104:32. He gave them hail for rain, a burning fire in the land.