50 The verb in this place is a preterite with the vav (ו) consecutive, judging from the pointing. It then follows in sequence the verb “you have found favor,” meaning you stand in that favor, and so it means “I have known you” and still do (equal to the present perfect). The emphasis, however, is on the results of the action, and so “I know you.”

In other versions

And the Lord said to Moses, “This very thing that you have spoken I will do, for you have found favor in my sight, and I know you by name.”

And the Lord said to Moses, “I will do the very thing you have asked, because I am pleased with you and I know you by name.”

The Lord answered Moses, “I will do this very thing you have asked, for you have found favor with me, and I know you by name.”

The Lord replied to Moses, “I will indeed do what you have asked, for I look favorably on you, and I know you by name.”

And Yahweh said to Moses, “Also I will do this thing that you have spoken, because you have found favor in my eyes and I have known you by name.”

And the Lord said unto Moses, I will do this thing also that thou hast spoken: for thou hast found grace in my sight, and I know thee by name.

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