69 Heb “in the eyes of.” This idiom usually means that someone will be treated well by the observer. It is unlikely that it means here that the Egyptians will like the Hebrews. Rather, it means that the Egyptians will give things to the Hebrews free—gratis (see 12:35–36). Not only will God do mighty works to make the king yield, but also he will work in the minds of the Egyptian people so that they will be favorably disposed to give Israel wealth.
70 The temporal indicator (here future) with the particle ki (וְהָיָה כִּי, véhaya ki) introduces a temporal clause.

In other versions

And I will give this people favor in the sight of the Egyptians; and when you go, you shall not go empty,

“And I will make the Egyptians favorably disposed toward this people, so that when you leave you will not go empty-handed.

And I will give these people such favor with the Egyptians that when you go, you will not go empty-handed.

And I will cause the Egyptians to look favorably on you. They will give you gifts when you go so you will not leave empty-handed.

And I will give this people favor in the eyes of the Egyptians, and then when you go, you will not go empty-handed.

And I will give this people favour in the sight of the Egyptians: and it shall come to pass, that, when ye go, ye shall not go empty:

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