16 The text simply has “evening, and you will know.” Gesenius notes that the perfect tense with the vav consecutive occurs as the apodosis to temporal clauses or their equivalents. Here the first word implies the idea “[when it becomes] evening” or simply “[in the] evening” ( §112.oo). Moses is very careful to make sure that they know it is Yahweh who has brought them out, and it will be Yahweh who will feed them. They are going to be convinced of this now.

In other versions

So Moses and Aaron said to all the people of Israel, “At evening you shall know that it was the Lord who brought you out of the land of Egypt,

So Moses and Aaron said to all the Israelites, “In the evening you will know that it was the Lord who brought you out of Egypt,

So Moses and Aaron said to all the Israelites, “This evening you will know that it was the Lord who brought you out of the land of Egypt,

So Moses and Aaron said to all the people of Israel, “By evening you will realize it was the Lord who brought you out of the land of Egypt.

And Moses and Aaron said to all the Israelites, “In the evening, you will know that Yahweh has brought you out from the land of Egypt,

And Moses and Aaron said unto all the children of Israel, At even, then ye shall know that the Lord hath brought you out from the land of Egypt:

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