50 The construction is unusual in that it says, “And Egypt will know.” The verb is plural, and so “Egypt” must mean “the Egyptians.” The verb is the perfect tense with the vav consecutive, showing that this recognition or acknowledgment by Egypt will be the result or purpose of the defeat of them by God.
51 The form is בְּהִכָּבְדִי (béhikkavédi), the Niphal infinitive construct with a preposition and a suffix. For the suffix on a Niphal, see §61.c. The word forms a temporal clause in the line.

In other versions

And the Egyptians shall know that I am the Lord, when I have gotten glory over Pharaoh, his chariots, and his horsemen.”

The Egyptians will know that I am the Lord when I gain glory through Pharaoh, his chariots and his horsemen.”

The Egyptians will know that I am the Lord when I receive glory through Pharaoh, his chariots, and his horsemen.”

When my glory is displayed through them, all Egypt will see my glory and know that I am the Lord!”

And the Egyptians will know that I am Yahweh when I display my glory through Pharaoh, through his chariots, and through his charioteers.”

And the Egyptians shall know that I am the Lord, when I have gotten me honour upon Pharaoh, upon his chariots, and upon his horsemen.

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